Petroleum Development Oman L.L.C.

Document title: Specification for Heating,

Ventilation and Air-Conditioning (HVAC)

Document ID SP-1285

Document Type Specification

Security Restricted

Discipline Civil Engineering

Owner UEP1C - Corporate Function Discipline Head

Issue Date October 2018

Version 5.0

Keywords: This document is the property of Petroleum Development Oman, LLC. Neither the whole
nor any part of this document may be disclosed to others or reproduced, stored in a retrieval system,
or transmitted in any form by any means (electronic, mechanical, reprographic recording or
otherwise) without prior written consent of the owner.

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i Document Authorisation

Authorised For Issue October 2018

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ii Revision History
The following is a brief summary of the 4 most recent revisions to this document. Details of all
revisions prior to these are held on file by the issuing department.

Version No. Date Author Scope / Remarks

Revision 0 July ‘90 W. Von Schmidt, First Issue
TTH/4
Revision 1 Mar ‘95 BEZ/5 Updated and Reformatted
Version 1.0 May ‘04 Ali Nasser Al Converted to Specification as per PDO
Jahadhamy, TTO/2 policy and minor changes to the text
(UEC)
Version 2.0 Dec ‘09 Ali Nasser Al Specification format and content
Jahadhamy, UIB/4 revised
(UEB)
Version 3.0 April , Hilal Said Al Aghbari HVAC specification revised here.
2013 UEP/1C (UEB) Other specification remain to be
followed from older revision 2.0
Version 4.0 March , Hilal Said Al Aghbari HVAC specification revised here.
2016 UEP/1C (UEB) Other specification remain to be
followed from older revision 3.0
Version 5.0 October, Hilal Said Al Aghbari HVAC specification revised here.
2018 UEP/1C (UEB) Other specification remain to be
followed from older revision 4.0

iii Related Business Processes

Code Business Process (EPBM 4.0)

iv Related Corporate Management Frame Work (CMF)

Documents
The related CMF Documents can be retrieved from the Corporate Business Control
Documentation Register CMF.

Version 4.0 March , Hilal Said Al Aghbari HVAC specification revised here.
2016 UEP/1C (UEB) Other specification remain to be
followed from older revision 3.0

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TABLE OF CONTENTS
i Document Authorisation ........................................................................................... 3
ii Revision History ........................................................................................................ 4
iii Related Business Processes .................................................................................... 4
iv Related Corporate Management Frame Work (CMF) Documents ........................... 4
Section 1: Introduction ................................................................................................................. 19
1 Introduction .............................................................................................................. 20
1.1 Purpose ......................................................................................................................... 20
1.2 User Guidelines.............................................................................................................. 20
1.3 Changes to the Specification ........................................................................................... 20
1.4 Specification Index ......................................................................................................... 20
Section 2: General Requirements .................................................................................................. 21
2.1 Introduction .............................................................................................................. 22
2.1.1 Purpose ......................................................................................................................... 22
2.1.2 Applicable Standards, Specifications and Codes ............................................................... 22
2.1.2.1 PDO Standards ............................................................................................................... 22
2.1.2.2 International Standards ................................................................................................... 23
2.1.2.3 SIEP / Shell GSI Standards ............................................................................................. 27
2.1.3 Compliance with Standards ............................................................................................. 27
2.1.4 Product / Asset Warranty ................................................................................................ 27
2.1.5 Quality Assurance and Control ........................................................................................ 28
2.1.6 Maintenance .................................................................................................................. 28
2.1.7 Factory Acceptance Test (FAT) ....................................................................................... 28
2.1.8 Guarantees ..................................................................................................................... 29
2.2 Scope ....................................................................................................................... 30
2.2.1 General.......................................................................................................................... 30
2.2.2 Units of Measurement ..................................................................................................... 30
2.2.3 Shop Drawings ............................................................................................................... 31
2.2.4 Protection and Storage .................................................................................................... 32
2.2.5 Painting, Colour Coding & Identification ......................................................................... 32
2.2.6 Test Points & Instruments ............................................................................................... 34
2.2.6.1 Test Points & Instruments for Pipe Works ........................................................................ 34
2.2.6.2 Test Points & Instruments for Ductwork .......................................................................... 35
2.2.7 Commissioning & Handover ........................................................................................... 35
2.2.7.1 Commissioning Programme ............................................................................................ 35
2.2.7.2 Pre-Commissioning ..................................................................................................... 36
2.2.8 Testing, Adjusting & Balancing ....................................................................................... 37
2.2.9 Test Report & Documentation Format .............................................................................. 38

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2.2.10 Spares, As-Built & Manual..............................................................................................38

2.2.10.1 Maintenance Tools .........................................................................................................38
2.2.10.2 As Built Drawings ..........................................................................................................38
2.2.10.3 Operating & Maintenance Manuals ..................................................................................39
2.2.10.4 Training .........................................................................................................................39
2.2.10.5 Coordination with Other Division ....................................................................................39
2.2.10.6 Existing Service and Equipment ......................................................................................40
2.3 Air-Conditioning & Ventilation Design General Specification ......................................41
2.3.1 General ..........................................................................................................................41
2.3.2 Design Criteria for Air Conditioning & Ventilation Works ................................................47
2.4 Specialist Areas .........................................................................................................51
2.4.1 Battery Rooms...............................................................................................................51
2.4.2 Control Rooms and Field Auxiliary Rooms ......................................................................51
2.4.3 Electrical Substations & Switch Houses ...........................................................................51
2.4.4 Gas Bottle Stores ............................................................................................................52
2.4.5 Kitchens........................................................................................................................52
2.4.6 Laboratories ..................................................................................................................53
2.4.7 Temporary Buildings .....................................................................................................53
2.5 Appendices .............................................................................................................54
Appendix 2.5A: Glossary of Definitions & Abbreviations ..........................................................55
2.5.A1 General Definitions & Terminology ..............................................................................55
2.5.A2 Abbreviations ...............................................................................................................56
2.5.A3 Abbreviations for Building Types .................................................................................58
2.5.A4 Abbreviations for Room Types ....................................................................................64
Appendix 2.5.B: Internal Environment Design Criteria .............................................................67
Appendix 2.5.C: Standard Forms: .................................................................................................71
2.5.C1 Test Report for Pipe Work Leakage (STD-2-1702-A01) ....................................................72
2.5.C2 Exceptions List (STD-2-1702-A02) .................................................................................73
2.5.C3 Handover Report (STD-2-1702-A03) ...............................................................................74
Section 3: Heating, Ventilation & Air-Conditioning Materials & Works ..........................................76
3.1 Introduction ...................................................................................................................77
3.2 Scope ............................................................................................................................77
3.2.1 General ..........................................................................................................................77
3.2.2 Abbreviations .................................................................................................................77
3.2.3 Definitions .....................................................................................................................77
3.2.3.1 General Definitions .........................................................................................................77
3.2.3.2 Specific Definitions ........................................................................................................78
3.2.4 Automation Controls.......................................................................................................79
3.2.5 Units of Measurement .....................................................................................................79
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3.3 Chilled Water System ..................................................................................................... 79

3.3.1 Air Cooled Water Chiller ................................................................................................ 79
3.3.1.1 General ....................................................................................................................... 79
3.3.1.2 Fluids............................................................................................................................ 80
3.3.1.3 Housing ...................................................................................................................... 80
3.3.1.4 Evaporator .................................................................................................................. 80
3.3.1.5 Condenser ................................................................................................................... 81
3.3.1.6 Compressor .................................................................................................................. 81
3.3.1.7 Capacity Modulation (Screw Compressor)....................................................................... 82
3.3.1.8 Refrigerant Circuit ......................................................................................................... 83
3.3.1.9 Electrical Requirements ................................................................................................. 83
3.3.1.10 Chiller Control ............................................................................................................... 84
3.3.1.11 Chiller Control Functions ............................................................................................... 84
3.3.1.12 Chiller Protection .......................................................................................................... 85
3.3.1.13 Remote Chiller Control Interface .................................................................................... 85
The chiller control system shall be suitable for the following remote control system interface
but not the limited from HVAC panel, DCS and Scada system: ............................................... 85
3.3.1.14 Flow Switch ................................................................................................................... 85
3.3.1.15 Motors .......................................................................................................................... 86
3.3.1.16 Building Control System Interface .................................................................................. 86
3.3.2 Pipe Work...................................................................................................................... 86
3.3.2.1 Chilled Water Pipe ......................................................................................................... 86
3.3.2.2 Refrigerant Pipe........................................................................................................... 87
3.3.2.3 Condensate Drain Pipe ................................................................................................ 87
3.3.3 Valves (Chilled Water) ................................................................................................... 87
3.3.3.1 Isolating Valves .......................................................................................................... 87
3.3.3.2 Double Regulating Valves ............................................................................................ 87
3.3.3.3 Chilled Water Commissioning Valve Sets ..................................................................... 87
3.3.3.4 Non-Return Valves ...................................................................................................... 87
3.3.3.5 Strainers ........................................................................................................................ 88
3.3.3.6 Terminal Units ............................................................................................................ 88
3.3.3.7 Safety Valves ................................................................................................................. 88
3.3.3.8 Air Cocks ...................................................................................................................... 88
3.3.3.9 Automatic Air Vents ....................................................................................................... 88
3.3.3.10 Drain Cocks ................................................................................................................... 88
3.3.3.11 Valves (Refrigerant) ....................................................................................................... 88
3.3.3.12 Fittings .......................................................................................................................... 89
3.3.4 Pipe Installation ............................................................................................................. 90
3.3.4.1 Pipe Work Installation Generally ..................................................................................... 90
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3.3.4.2 Pipe work Support ..........................................................................................................92

3.3.4.3 Horizontal Piping ...........................................................................................................92
3.3.4.4 Vertical Piping Supports: ................................................................................................93
3.3.4.5 Support Insulators...........................................................................................................94
3.3.4.6 Trenches ........................................................................................................................94
3.3.4.7 Refrigerant Pipe Work ....................................................................................................94
3.3.4.8 Condensate Drains Pipe Work .........................................................................................95
3.3.5 Pipe Insulation ...............................................................................................................95
3.3.5.1 Chilled Water Pipe Insulation ..........................................................................................95
3.3.5.2 Refrigerant Pipe-Work Insulation ....................................................................................95
3.3.5.3 Condensate Drain Pipe-Work Insulation ...........................................................................95
3.3.6 Execution.......................................................................................................................95
3.3.7 Pre-insulated Chilled Water Pipes ....................................................................................96
3.3.8 Chilled Water Pumps ......................................................................................................98
3.3.9 Pre-commissioning Cleaning Of Pipe Work ......................................................................99
3.3.10 Chilled Water Pressurisation Units ...................................................................................99
3.3.11 Chemical Dosing ..........................................................................................................100
3.4 Air handling system ......................................................................................................101
3.4.1 Air Handling Units .......................................................................................................101
3.4.1.1 General ........................................................................................................................101
3.4.1.2 Components .................................................................................................................101
3.4.1.3 Casing .........................................................................................................................101
3.4.1.4 Fan and Motor ..............................................................................................................102
3.4.1.5 Cooling Coil (Chilled Water & DX type)........................................................................103
3.4.1.6 Moisture Eliminators ....................................................................................................103
3.4.1.7 Electrical Heaters .........................................................................................................103
3.4.1. 8 Humidifiers ..................................................................................................................104
3.4.1.9 Mixing Box ....................................................................................................................105
3.4.1.10 Filter ...........................................................................................................................105
3.4.1.11 Sand trap louver with filter ...........................................................................................107
3.4.1.12 Weather hood (for outdoor AHU) .................................................................................107
3.4.1.13 Heat Exchangers & Energy Recovery System .................................................................107
3.4.2 Variable Air Volume (VAV) Units ................................................................................109
3.4.2.1 General .........................................................................................................................109
3.4.2.2 Electronic Modulating Control ......................................................................................110
3.4.3 Constant Air Volume (CAV) Units ................................................................................110
3.4.4 Fan Coil Units ..............................................................................................................110
3.4.4.1 General ........................................................................................................................110
3.4.4.2 Materials .....................................................................................................................112
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3.4.4.2.1 Unit Chassis ................................................................................................................ 112

3.4.4.2.2 Fan /Motor .................................................................................................................. 112
3.4.4.2.3 Coil ............................................................................................................................ 112
3.4.4.2.4 Drain Pans................................................................................................................... 112
3.4.4.2.5 Electric Heaters ........................................................................................................... 113
3.4.4.2.6 Controls ...................................................................................................................... 113
3.5 Central Direct Expansion Units (Condensing Unit) ......................................................... 113
3.5.1 General ....................................................................................................................... 113
3.5.2 Materials ..................................................................................................................... 114
3.5.2.7 Execution ................................................................................................................ 115
3.6 Unitary Air Conditioning Unit ....................................................................................... 115
3.6.1 Window Air Conditioners ............................................................................................. 115
3.6.2 Mini Split Units ........................................................................................................... 116
3.6.2.1 General ..................................................................................................................... 116
3.6.2.2 Evaporator Unit ........................................................................................................ 116
3.6.2.3 Condensing Unit ............................................................................................................. 117
3.6.2.4 Control .................................................................................................................... 117
3.6.3 Cassette Type Fan Coil Unit .......................................................................................... 117
3.6.4 Packaged Air Conditioning Units ................................................................................... 118
3.6.4.1 General........................................................................................................................ 118
b) Condenser Fan: The condenser fan shall be of the direct driven, propeller type, with
corrosion resistant blades riveted to corrosion resistant steel spiders. It shall be dynamically
balanced and discharge air vertically with protective grilles. Motor shall be three phase with
permanently lubricated ball bearing, built in current and thermal over-load protection, and
weather tight lingers over bearings. ........................................................................................ 119
3.6.4.5 Coils........................................................................................................................... 119
3.6.4.6 Refrigerant Circuit and Components .......................................................................... 120
3.6.4.7 Filter Section ............................................................................................................... 120
3.6.4.8 Controls and Safeties ..................................................................................................... 120
3.6.4.9 Motor .......................................................................................................................... 120
3.6.5 Variable Refrigerant Flow/Volume (VRF/VRV) System ................................................. 120
3.6.5.1 General .................................................................................................................... 120
3.6.5.2 Outdoor Unit ............................................................................................................ 121
3.6.5.2.1 Compressor ................................................................................................................. 121
3.6.5.2.2 Heat Exchanger ........................................................................................................... 121
3.6.5.2.3 Refrigerant Circuit ....................................................................................................... 121
3.6.5.2.4 Safety Devices ............................................................................................................. 122
3.6.5.2.5 Oil Recovery System ................................................................................................... 122
3.6.5.3 Indoor Unit .................................................................................................................. 122
3.6.5.4 Control ....................................................................................................................... 122
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3.6.5.5 Central Remote Controller.............................................................................................122

3.6.5.6 Unified On/Off Controller. ...........................................................................................123
3.6.5.7 Schedule Timer ...........................................................................................................123
3.7 Fans ............................................................................................................................123
3.7.1 General ........................................................................................................................123
3.7.2 Products.......................................................................................................................124
3.7.2.1 Centrifugal Fans ..........................................................................................................125
3.7.2.2 Axial Flow Fans ..........................................................................................................126
3.7.2.3 Propeller Fans .............................................................................................................126
3.7.2.4 Wall/Window Mounted Extract Fans .............................................................................126
3.7.2.5 Ducted Inline Extract Fans ............................................................................................126
3.7.2.6 Twin Fans ...................................................................................................................127
3.7.2.7 Roof Extract Units ......................................................................................................127
3.7.2.8 Explosion Proof Exhaust Fan Ducted Type. ....................................................................128
3.7.2.9 Explosion Proof Exhaust Fan Wall Mounted Type ..........................................................128
3.8 Duct Work ...................................................................................................................128
3.8.1 General ........................................................................................................................128
3.8.1.1 Quality Assurance, Code and Standards .........................................................................129
3.8.1.2 Submittals .................................................................................................................129
3.8.1.3 Delivery Storage and Handling ......................................................................................129
3.8.2 Materials...........................................................................................................................130
3.8.2.1 Sheet Material ............................................................................................................130
3.8.2.2 Flexible Duct Work ....................................................................................................130
3.8.2.3 Flexible Connections ...................................................................................................131
3.8.2.4 Pre-insulated Phenolic Duct Work ................................................................................131
3.8.2.5 Volume Control Damper (Balancing Dampers) .............................................................131
3.8.2.6 Fire Dampers ..............................................................................................................132
3.8.2.6.1 Curtain Type: ..............................................................................................................133
3.8.2.6.2 Smoke Dampers ...........................................................................................................133
3.8.2.6.3 Combination Fire/Smoke Dampers: ..............................................................................133
3.8.2.7 Access Panels...............................................................................................................134
3.8.2.8 Motorized Shut off Dampers. ........................................................................................135
3.8.2.9 Back Draft Dampers. ....................................................................................................135
3.8.2.10 Pressure Relief Dampers ...............................................................................................135
3.8.2.11 Duct Mounted Electric Heater .......................................................................................135
3.8.2.12 Duct Work Flanges .......................................................................................................136
3.8.2.13 Turning Vanes..............................................................................................................136
3.8.2.14 Sound Attenuator ..........................................................................................................136
3.8.2.15 Air Flow Pressure Switch .............................................................................................137
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3.8.3 Air Outlets and Inlets .................................................................................................... 137

3.8.3.1 General........................................................................................................................ 137
3.8.3.2 Linear Bar Grilles ......................................................................................................... 137
3.8.3.3 Four-way Ceiling Diffusers .......................................................................................... 138
3.8.3.4 Wall Registers .............................................................................................................. 138
3.8.3.5 Circular Ceiling Diffusers ............................................................................................. 138
3.8.3.6 Linear Slot Diffusers.................................................................................................... 138
3.8.3.7 Extract Air Louvers ..................................................................................................... 138
3.8.3.8 Sand Trap Louvre for Fresh Air Intake ........................................................................... 139
3.8.4 Duct Construction and Installation ................................................................................. 139
3.8.4.1 General ....................................................................................................................... 139
3.8.4.2 Duct supports .............................................................................................................. 140
3.8.4.3 Cleaning ..................................................................................................................... 141
3.8.4.4 Test Holes................................................................................................................... 141
3.8.4.5 Testing, Balancing and Commissioning.......................................................................... 141
3.8.5 Duct Insulation and Liner .............................................................................................. 141
3.8.5.1 Thermal Insulation ...................................................................................................... 142
3.8.5.3 Adhesive and Fastener Materials ................................................................................... 143
3.8.5.3.1 Liner Adhesive ........................................................................................................... 143
3.8.5.3.2 Mechanical Fasteners .................................................................................................. 143
3.8.6 Sealing Materials ......................................................................................................... 143
3.8.7 Fire-Stopping ............................................................................................................... 144
3.8.8 Silencers (Sound Attenuator) ......................................................................................... 144
3.9 Power and Automation Control ..................................................................................... 144
3.9.1 General........................................................................................................................ 144
3.9.2 Design ........................................................................................................................ 145
3.9.3 Functional Description of Control System: ..................................................................... 147
3.9.4 Material ....................................................................................................................... 148
3.9.5 Control and Monitoring Philosophy for Direct Expansion System. ....................................... 150
3.9.5.1 AHU Fan Start/Stop & Monitoring ................................................................................. 151
3.9.5.2 Temperature Control ................................................................................................... 152
3.9.5.3 Alarm Monitoring ...................................................................................................... 152
3.9.5.4 Change Over Philosophy ................................................................................................ 152
Air Handling Unit/Package Uint ................................................................................................. 152
Battery Room Extract Fan .......................................................................................................... 152
3.9.5.5 Motorized Fire and Smoke Damper (MFSD).................................................................... 153
3.9.5.6 Maximum Allowable Running Time for Motorised Dampers ............................................ 153
Type of damper ......................................................................................................................... 153
Location 153
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Opening time.............................................................................................................................153
(Seconds) ..................................................................................................................................153
Closing Time (Seconds) .............................................................................................................153
Remarks 153
3.9.6 Standards Control Interlocks..........................................................................................153
3.9.7 Alarms on Local Control Boards ....................................................................................154
3.9.8 Building Management System (BMS) ............................................................................154
3.9.9 Electrical Connections .................................................................................................155
3.9.10 Electrical Power Supply and Electrical Safety .................................................................156
3.9.11 Start-up and Commissioning..........................................................................................156
3.10 Cold Room ..................................................................................................................156
3.10.1 General ........................................................................................................................156
3.10.2 Room Construction .......................................................................................................156
3.10.3 Refrigeration Plant for Cold Rooms and Freezer Rooms .................................................158
3.10.4 Refrigeration Electrical Work ........................................................................................160
3.11 Water Cooler ................................................................................................................160
3.11.1 Bottle Water Type Water Cooler Units ...........................................................................161
3.12 Ice Maker.....................................................................................................................162
Ice maker shall have the standard features as following: .......................................................162
3.13 Refrigerator..................................................................................................................163
3.13.1 Deep Freezer ...................................................................................................................164
3.14 Testing & Commissioning .............................................................................................164
3.14.1 General ........................................................................................................................164
3.14.2 Test Instruments ...........................................................................................................165
3.14.3 Testing & Commissioning Procedures ............................................................................165
3.14.4 Chilled Water..............................................................................................................166
3.14.4.1 Leakage Testing of Pipe Works .....................................................................................166
3.14.5 Air Systems .................................................................................................................169
3.14.6 Control Systems ...........................................................................................................171
3.14.7 Final Balance & Calibration ..........................................................................................172
3.15 Supervision ..................................................................................................................172
Section 4: Electrical Specification for Heating, Ventilation & Air-Conditioning .............................174
4.1 Abbreviations ...............................................................................................................175
AC Alternating Current .............................................................................................175
ACB Air Circuit Breaker .............................................................................................175
Amp Ampere ...............................................................................................................175
CBCT Core Balance Current Transformer ..................................................................175
SCADA Supervisory Control and Data Acquisition ..........................................................176
SFU Switch Fuse unit ................................................................................................176
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SP PDO Specification .............................................................................................. 176

SWA Steel Wire Armoured ......................................................................................... 176
UPS Un-interrupted Power Supply............................................................................. 176
V Voltage ............................................................................................................... 176
VSD Variable Speed Drive System ............................................................................ 176
XLPE Cross-linked polyethylene................................................................................. 176
4.2 Electrical Requirements ................................................................................................ 177
4.2.1 HVAC equipment for building shall be fed from the HVAC MCC as per PDO electrical
specification. Company shall provide redundant incoming power supply to the HVAC MCC.
From HVAC MCC to all electrical downstream system required for successful operation of the
HVAC system shall be in scope of HVAC Contractor / Vendor. ............................................. 177
4.2.2 Single point 240V AC, 50 Hz power supply (UPS supply preferred if available) shall
be supplied to HVAC DDC (Direct Digital Control) panel in addition to one normal 240V 50 Hz
power supply required for the utilities of DDC like heaters, fans, panel lights and sockets as
applicable. ............................................................................................................................... 177
4.2.3 The power and control circuits shall be physically segregated by housing them in
separate compartments. ......................................................................................................... 177
4.2.4 Hazardous area classification shall be ‘safe’ and degree of protection shall be IP55
and IP41 for all outdoor and indoor electrical equipments respectively. However, for battery
room, the exhaust fans shall be suitable for Zone 1, Gas Group IIC, T4. .............................. 177
4.2.5 A plant earthing system shall be provided by others. All electrical and mechanical
equipments including condensing unit and air handling unit shall be provided with two
diagonally opposite earthing points (to be provided by HVAC Contractor /Vendor) on the unit.
These units shall be bonded to the plant earthing system by HVAC Contractor /Vendor using
Yellow / Green PVC cable size as mentioned in Clause 3.2 (Appendix-2) of SP-1109. ........ 177
4.2.6 The condensing units along with all electrical, instrumentation shall be suitable for
outdoor installation without sunshade. All HVAC condensing unit, Heaters for AHU, AHU’s,
Chillers and exhaust fans working / stand by selection shall be controlled automatically by
DDC system. ........................................................................................................................... 177
4.2.7 All the electrical equipments viz. motors and instrumentation located outdoors shall
be suitable for 82°C black bulb temperature. All electrical equipments that are not in the air
conditioned environment like substation building shall be designed for an ambient
temperature of 55°C. All electrical equipments located in shade shall be suitable for 55°C
shade temperature. It is to be noted that shade effect shall not be considered for some of the
motors viz. fresh air fan motor, motors of volume control dampers. Also Vendor to check and
confirm that motors in condensing units and air handling units are in sheet metal enclosure of
respective units and hence can be treated as “under shade”. Such motors shall be suitable for
55°C. 177
4.2.8 Final paint shade of all electrical equipment shall be RAL7035. ............................... 177
4.2.9 Also refer SP-1285 for additional electrical details. ................................................... 177
4.2.10 Make of all electrical equipment shall be as per Company approved Vendor list
(AVME) except those motors not forming part of AHU........................................................... 177
4.3 415V HVAC MCC ...................................................................................................... 178
4.3.1 HVAC equipment for the building shall be fed from dedicated 415V LV HVAC MCC as
per PDO electrical specification. ............................................................................................. 178
4.3.2 The 415V LV HVAC MCC shall be in full compliance with requirements of SP-1121,
SP-1103, DEP 33.67.01.31-Gen., DEP 33.64.10.10-Gen. and standard drawings referred in
these specifications like S67.004 & S67.019. ........................................................................ 178

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4.3.3 The 415 V Circuit breakers / contactors shall be Air Insulated Type. .......................178
4.3.4 The 415 V LV HVAC MCC shall be as per the technical requirements specified in
data sheet and site climatic conditions referred in this document. .........................................178
4.3.5 The 415V LV HVAC MCC shall be metal enclosed, metal clad with Form-4 type
construction. All the incoming and outgoing feeders shall be of draw out type (Except for the
group single phase outgoing feeders). The busbar cover shall be with bolted enclosure
(cover); however cable alley cover shall be with hinged enclosure (cover). ..........................178
4.3.6 Final paint shade for HVAC MCC & control panel shall be RAL 7035. .....................178
4.3.7 The 415V LV HVAC MCC shall have two incomers and one bus coupler without
changeover arrangement, all with load break switch (LBS) with 2 out of 3 mechanical interlock
arrangement. Each LBS shall be rated for the 100% load requirement of HVAC Equipment.
178
4.3.8 The 415 V LV HVAC MCC shall be Single front type and shall have only front access
as the 415 LV HVAC MCC shall be installed flushed to the wall from rear side. ...................178
4.3.9 Where the rating of the LV circuit (excluding motor feeders) is 100A and above, in
order to ensure proper protection coordination, current limiting type MCCB with LSIG
protection release shall be provided. Protection coordination with upstream MCCB / ACB and
downstream MCCB / fuse shall be ensured. Earth fault protection is required for feeder rating
100 Amp and above. ...............................................................................................................178
4.3.10 Feeder for Motor rated 30kW and above shall be provided with Core Balance Current
Transformer (CBCT) and earth fault relay. .............................................................................178
4.3.11 All motor starter modules in MCC shall have Switch fuse unit (SFU) and Remote
Control Unit (RCU) shall be provided near to the motors for local operation and maintenance.
In addition motors rated 75kW and above shall be provided with space heater / anti
condensation heater. Safety switch shall be provided for space heaters close to the motor.178
4.3.12 Feeder for Motor rated up to and including 2.2kW shall have in line RCU with direct
reading ammeter arrangement. ..............................................................................................178
4.3.13 For motor feeders; rating of contactor, overload relay, fuse, fuse base & components
shall be selected by Vendor to conform to Type-2 coordination as specified in IEC 60947-4-1.
179
4.3.14 All motor feeders shall have SFU, contactor and thermal overload relay. ................179
4.3.15 Motor starter as well as power feeder module in HVAC MCC shall be provided with
pad lock facility. .......................................................................................................................179
4.3.16 For all Power feeders, LBS with pad lock facilities shall be provided near the package
equipment for local Isolation. ..................................................................................................179
4.3.17 The rating of any fuse protected LV circuit which derives power supply from the 415V
switchboard should not exceed 25% of the rating of the transformer incomer to the
switchboard or 100A, whichever is lower. Similarly, the rating of any fuse-protected LV-circuit
which derives power supply from a 415V DB should not exceed 50% of the rating of the fuse
protected 415V incomers to the distribution board. ................................................................179
4.3.18 All indicating lamps, metering and control switches shall be in line with PDO
standards. ...............................................................................................................................179
4.3.19 Electrical heaters and Thyristor Control Panel shall be in accordance to DEP
33.68.30.33-Gen as applicable. ..............................................................................................179
4.3.20 AC electrical Variable Speed Drive system shall be in accordance to DEP
33.66.05.33-Gen. ....................................................................................................................179
4.3.21 The 415V LV HVAC MCC shall be designed so as to facilitate extension on both
sides. 179
4.3.22 20% spare terminals shall be provided in the terminal block. ...................................179
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4.3.23 Cable entries to the 415V LV HVAC MCC shall be from bottom. 415V LV HVAC MCC
shall be provided with un-drilled gland plate of adequate size, for fixing cable gland. 415V LV
HVAC MCC shall be provided with cable glands, lugs etc. .................................................... 179
4.3.24 The draw out portion of all the modules of a particular type and rating shall be
completely identical and interchangeable............................................................................... 179
4.3.25 The short circuit rating of the 415V HVAC MCC shall be min 50kA for 1 sec or as per
project specific requirement whichever is higher. ................................................................... 179
4.3.26 Power/control cables shall be supplied by HVAC Contractor / Vendor except incoming
power supply cable to HVAC MCC and 240V AC supply cable to DDC panel. Power/control
cables shall be Cu/XLPE/SWA/PVC type. Single core cables shall be Cu/XLPE/AWA/PVC.
Sizing of cables shall be done in such a way that steady state and dynamic voltage drops
shall not exceed the limits specified DEP 33.64.10.10-Gen. ................................................. 179
4.3.27 Power supply to Exhaust fans in Toilets /Bathrooms / Pantry shall not be powered
from HVAC panel. Same shall be powered from Lighting and Small Power Distribution board.
However, exhaust fans in Battery room, Mess & Kitchen shall be powered and controlled from
HVAC panel. ........................................................................................................................... 180
4.3.28 All Air Heaters wherever required shall be provided with local safety switch (for single
phase heater) or Load Break Switch (for three phase heater) pad lockable type in off position
for Isolation. ............................................................................................................................ 180
4.3.29 Local / Remote switch shall be provided in DDC panel. No Local / Remote switch
shall be provided in Motor modules. In local mode, it shall be possible to operate and maintain
any motor from local RCU and Load Break Switch as the case may be. .............................. 180
4.3.30 Corresponding to each AHU, dampers shall have on/off switches to enable local
maintenance of associated motors. ........................................................................................ 180
4.3.31 Load Break Switch / RCU for local Isolation (pad lockable type in off position) near the
unit shall be provided for following HVAC systems: ............................................................... 180
4.3.32 Window AC ................................................................................................................ 180
4.3.33 Split AC - Local Isolation required for both Indoor unit as well as Outdoor unit ........ 180
4.3.34 VRV Units ( Variable Refrigerant Volume) - Local Isolation required for both Indoor
unit as well as Outdoor unit .................................................................................................... 180
4.3.35 Package AC Units - Local Isolation required near the unit ....................................... 180
4.3.36 Condensing Unit and AHU - Local Isolation required for condensing unit. Remote
control unit (RCU) is required for each AHU motors. If motors are provided with space heater
(>= 75kW) then safety switch near motor is also required for local Isolation. ........................ 180
4.3.37 AHU - Remote control unit (RCU) is required for each AHU motors. If motors are
provided with space heater (>= 75kW) then safety switch near motor is also required for local
Isolation. .................................................................................................................................. 180
4.3.38 Chilled Water System - Local Isolation required near the unit. ................................. 180
4.4 Motors ........................................................................................................................ 180
4.4.1 All AHU motors shall be in line with SP-1119, SP-1103, DEP 33.66.05.31-Gen and
DEP-33.64.10.10-Gen and shall be procured from PDO AVME list. All other motors shall
comply with IEC 60034-1, IEC 60034-5, IEC 60034-12 and IEC 60034-14 and 60034-18. .. 180
4.4.2 The cage induction type motors forming part of an AC Variable Speed Drive System
(VSDS) shall comply with DEP 33.66.05.33-Gen, as applicable. .......................................... 180
4.4.3 All motors rated 75kW and above shall be designed complete with anti-condensation
space heaters (240V, single phase, 50Hz) for use when motors are out of service. The anti-
condensation space heaters shall be engaged automatically when the motors are stopped
and de-energized. Safety switch shall be provided near to motor for anti-condensation space

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heater. The anti-condensation heater terminal shall be provided in separate terminal box on
motor. 181
4.4.4 The cooling system for all the motors shall be provided in accordance to IEC. ........181
4.4.5 Ingress protection for motor enclosure & terminal boxes shall be IP 55. ..................181
4.4.6 All insulation materials shall be Class F, as defined in IEC 60034-18. The rating of the
machine offered by the Manufacturer shall be based on a Class B temperature rise for all
parts of the machine windings. ...............................................................................................181
4.4.7 The sound pressure level of the loaded machine shall not exceed 77 dB(A) in the
work area, measured in accordance with ISO 1680. ..............................................................181
4.4.8 Minimum efficiency at full load of LV motors shall comply with IE2 (High efficiency) of
IEC60034-30 ...........................................................................................................................181
4.4.9 Final paint shade for motor shall be RAL 7035. ........................................................181
4.4.10 Motor body shall be provided with two (2) diagonally opposite earthing bosses. The
motor terminal box shall have separate earthing arrangement. .............................................181
4.4.11 All motors shall be rated less than 160 KW and voltage levels shall be in line with SP-
1103 Appendix 2. ....................................................................................................................181
4.5 Exhaust Fan ...............................................................................................................181
4.5.1 Wall mounted exhaust fans, 2 Nos (1 working + 1 stand by) for each battery room
shall be provided. Each fan shall be provided with electric motor. .........................................181
4.5.2 Battery room fans shall be explosion proof and shall be provided with motors suitable
for Zone 1, T4 rating, Gas Group IIC, T4, high efficiency, totally enclosed with Class 'F'
insulation. Terminal box for exhaust fans shall be explosion proof type ................................181
4.5.3 Only one exhaust fan shall be running any point of time. In case of failure of one fan,
the other shall start automatically. ..........................................................................................181
4.5.4 Exhaust fan shall be manufactured in weather resistant polymeric material and shall
be designed for maximum aerodynamic efficiency. ................................................................181
4.5.5 The fan shall be suitable for operation in ambient temperature up to 55⁰C and shall
be fitted with thermal overload protection trip. ........................................................................181
4.5.6 The fan shall be of integrated component design allowing all parts to be dismantled
for cleaning without the use of specialist tools. ......................................................................182
4.5.7 Fan shall have a wall louver and shall be provided with back draught damper. .......182
4.5.8 Capacity of exhaust fan shall be as per approved sizing calculations. .....................182
4.6 Interface with Other Systems Like FCS/FGS/IPS/SCADA/UPS etc .........................182
4.6.1 DDC shall have provision to receive potential free contacts from building fire alarm
system or F & G system to trip the entire HVAC system. .......................................................182
4.6.2 HVAC common Fault Alarm i.e. Failure of both HVAC units (Potential Free dry
Contact) from DDC to SCADA and FCS.................................................................................182
4.6.3 HVAC Unit Fault Alarm i.e. Failure of each HVAC units (Potential Free dry Contact)
from DDC to SCADA and FCS. ..............................................................................................182
4.6.4 Potential free contacts for battery room exhaust fan failure (if both fan fails) from DDC
panel to each AC and DC UPS unit to inhibit boost charge operation of battery bank. .........182
4.6.5 Potential free contacts for battery room exhaust fan failure (if any one fan fails) from
DDC panel to SCADA and FCS. .............................................................................................182
4.6.6 Common Fault alarm from HVAC MCC (combination of all electrical faults within
MCC) to SCADA and FCS. .....................................................................................................182

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4.6.7 Signals to SCADA are applicable in case of standalone electrical substations and
FCS in case of process control building. ................................................................................ 182
4.7 Electrical Documents ................................................................................................. 182
4.7.1 Vendor shall submit the following electrical documents as a minimum along with bid.
182
4.7.2 GA drawing – 415V LV HVAC MCC with cable entry and mounting details. ............ 182
4.7.3 GA drawings – DDC panel, Heater panel, VSD etc .................................................. 182
4.7.4 Single Line diagram - 415V LV HVAC MCC ............................................................. 182
4.7.5 Single Line diagram - VSD, Heater Panels as applicable. ........................................ 182
4.7.6 Filled in data sheets for 415V LV HVAC MCC, motors, Exhaust fan, Heater and VSD
as applicable. .......................................................................................................................... 183
4.7.7 HVAC Package and Duct layout ................................................................................ 183
4.7.8 Sub-Vendor list (for electrical equipments) ............................................................... 183
4.7.9 Vendor shall submit the following electrical documents after Purchase Order (during
detail engineering): ................................................................................................................. 183
4.7.10 Load list indicating maximum demand figures with rated power, absorbed power,
efficiency and power factor for various loads of HVAC. (indicating working / standby
operation) ................................................................................................................................ 183
4.7.11 GA drawing - 415V LV HVAC MCC with cable entry and mounting details. ............. 183
4.7.12 GA drawings – DDC panel, Load Break Switch, RCU, Safety switch, Heater panel,
VSD etc with cable entry and mounting details. ..................................................................... 183
4.7.13 415V LV HVAC MCC - Single Line diagram, Wiring / Schematic drawings with
protection and metering, Bill of materials ............................................................................... 183
4.7.14 VSD - Single Line diagram, Wiring / Schematic drawings with protection and
metering, Bill of materials ....................................................................................................... 183
4.7.15 Heater Panel - Single Line diagram, Wiring / Schematic drawings with protection and
metering, Bill of materials ....................................................................................................... 183
4.7.16 DDC Panel - Single Line diagram, Wiring / Schematic drawings with protection and
metering, Bill of materials ....................................................................................................... 183
4.7.17 Filled in data sheets for 415V LV HVAC MCC, motors (including performance curves),
Exhaust fan, Heater and VSD as applicable. ......................................................................... 183
4.7.18 HVAC Package and Duct layout ................................................................................ 183
4.7.19 Cable sizing calculations ........................................................................................... 183
4.7.20 Cable Schedule ......................................................................................................... 183
4.7.21 Interconnection diagram with cable termination details including terminal numbers of
each equipment ...................................................................................................................... 183
4.7.22 Cable route layout ...................................................................................................... 183
4.7.23 Hazardous Area Certificates ( applicable for exhaust fans) ...................................... 183
4.7.24 Inspection and test plans (for electrical equipments) ................................................ 183
4.7.25 Test Procedures (for electrical equipments) .............................................................. 184
4.7.26 Routine test reports (for electrical equipments) ......................................................... 184
4.7.27 Sub-Vendor list (for electrical equipments) ............................................................... 184
5.0 Appendices ............................................................................................................. 185

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Appendix A: HVAC Typical and General Details ..........................................................186

Appendix B: Standard Air Conditioning Test Sheets ....................................................199
4.9 Appendix C: SP User - Comment Form ....................................................................215

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Section 1: Introduction

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1 Introduction
1.1 Purpose
The purpose of this document is to specify the minimum requirements for “HVAC
Works” and is intended for use by PDO and its nominated Consultants and
Contractors for the development and operation of Company facilities.
This specification is intended to:
- Set the Company standards for facilities along the facilities life cycle.
- Disseminate and record facilities related information, experience and
procedures.
1.2 User Guidelines
This Specification supersedes the HVAC related contents of the SP-1275 Version 2.0
‘specification and Criteria for design of Civil & Building Works’ and the SP-1285
Version 4.0 ‘Specification for Building Services. All other contents of these
specification -apart from the HVAC contents- remains unchanged and needs to be
followed as on version 2.0 until further revision announced .Other than the conversion
or formatting, the following are the main changes to this document.
- HVAC services specifications are covered in this document under section 1, 2
& 3.
- Various referenced international standards are revised to latest requirements.
Applicable Standards, Specifications are revised.
For all HSE requirements, the User shall refer the CP-122 Code of Practice for
‘Health, Safety and Environmental Protection’ and other documents referenced
therein.
The User should use this document, SP-1285 Specification for HVAC Services’ and
only the relevant parts of this specification, for a particular contract.
1.3 Changes to the Specification
Custodian of this document is the Corporate Functional Discipline Head (CFDH) of
Civil Engineering. Any User of this document, who encounters an inaccuracy or
ambiguity, is requested to notify the CFDH using the SP user-comment form provided
in Appendix-C of Section-3.
Reviews and modifications or changes to the specification will normally be made by
the CFDH every four years or earlier when justified.
1.4 Specification Index

This Specification comprises of the following Chapters:

Section 1 : Introduction
Section 2 : General Requirements
Section 3 : Heating, Ventilation & air-Conditioning Materials &
Work.
The User should issue only the relevant Chapters of this Specification, for a particular
contract.

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Section 2: General Requirements

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2.1 Introduction

This specification covers the General requirements for the design, furnishing
&installation of equipment, final testing, adjusting, and balancing of all heating,
ventilating and air-conditioning system.
2.1.1 Purpose

The purpose of this document is to specify the minimum requirements for “Heating,
Ventilating and Air Conditioning” (HVAC) Works and is intended for use by PDO and
its nominated Consultants and Contractors for the development and operation of
Company facilities.
This specification is intended to:
- Set the Company standards for facilities along the facilities life cycle.
- Disseminate and record facilities related information, experience and
procedures.
This part shall be read in conjunction with other services of the Building and Utility
Services specification.
2.1.2 Applicable Standards, Specifications and Codes

This document shall be read in conjunction with the latest revisions of the following
standards, Specifications and Codes.
2.1.2.1 PDO Standards

SP 1100 : Specification for Testing and Commissioning of

Electrical Equipment
SP 1119 : Specification for electrical Machines cage induction
type.
SP 1173 : Specification for ‘Welding of On-Plot Pipe work’
SP 1176 : Specification for Non Destructive Examination
(Amend/supplements to ASME BPV Code section V)
SP 1231 : Health, Safety and Environment Specification
(Occupational Health)
SP 1246 : Specification for Painting and Coating of Oil & Gas
Production Facilities
SP 1275 : Specification and Criteria for Design of Civil &
Buildings
SP 1279 : Specification for ‘Civil & Building Construction’
SP 1284 : Specification for Signs & Signboards – Standard
Signs Catalogue
GU 628 : Guide to Civil & Buildings Standard Drawings - Index
CP 122 : Code of Practice for ‘Health, Safety & Environmental
Protection’

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2.1.2.2 International Standards

British Standards (BS)
BS 2971 : Class II Arc Welding.
BS EN 287 : Qualification test of welders. Fusion welding. Steels.
BS 6031 : Code of Practice for Earthworks
BS EN 287 : Approval Testing of Welders for Fusion Welding
ASME IX : Boiler & Pressure Vessel Code IX Welding & Brazing
Qualifications
AWS D1.1 : Structural Welding Code – Steel
IP 15 : Institute of Petroleum Model Code of Practice Part 15 –
‘Area Classification Code for Petroleum Installations’
BS ISO 8501 : Preparation of Steel Substrates Before Application of
Paints & Related Products - Visual Assessment of
Surface Cleanliness
IEC : International Electro technical Commission (IEC)
Standards.
IEC 60364 : Electrical Installation of Buildings
IEC 60439-4 : Low voltage switchgear and control gear assemblies
IEE : Institute of Electrical Engineers (IEE) Regulations for
Electrical Installations.
CIBSE : Chartered Institution of Building Services Engineers
(CIBSE) Guide. BS 4871: Part 1
BS 759 : Valves, Gauges & Other Safety Fittings.
BS 3974 : Specification for pipe supports.
BS 5970 : Code of practice for thermal insulation of pipe and
equipment.
BS EN 1057 : Copper & Copper Alloy Tubes for heating
application.
BS EN10255 : Non-alloy steel tubes suitable for welding and
threading.
BS EN 12449 : Copper & Copper Alloy Tubes for general purposes.
BS EN 12451 : Copper & Copper Alloy Tubes for heat exchangers
BS 2879 : Draining Taps
BS EN 1452 : UPVC Pressure Pipes for Cold Potable Water
BS EN 10216-1 : Seamless steel tubes for pressure purposes.

BS EN 10217-1 : Welded steel tubes for pressure purposes.

BS EN 1171 : Cast Iron Gate Valves

BS EN 13789 : Cast Iron Globe Valves

BS EN 12334 : Industrial valves. Cast Iron Check Valves.

BS EN 12288 : Copper Alloy Gate Valves.

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BS 9999 : Code of practice for fire safety in the design,

management and use of buildings
BS EN 779 : Particulate Air Filtres for General Ventilation
BS EN 61260 : Electro acoustics, Octave-band, and fractional
octave-band filters
BS EN 61672 : Electro acoustics. Sound level meters
BS EN 60942 : Electro acoustics, Sound Calibrators
HVCA : Heating & Ventilation Contractors Association
Publications
Air Conditioning and Refrigeration Institute (ARI)
ARI 210 : Unitary Air Conditioning Equipment
ARI 270 : Standard for sound rating of outdoor unitary
equipment
ARI 360 : Commercial and Industrial Unitary Air-conditioning
equipment
ARI 370 : Sound Rating of Large Outdoor Refrigerating and Air-
Conditioning Equipment.
ARI 410 : Forced circulation Air-cooling and Air-heating coils
ARI 430 : Central Station Air-handling Unit
ARI 495 : Refrigerant Receivers.
ARI 550 / 590 : Standard for Water Chiller Packages using Vapour
compression.
ARI 650 : Standard for Air Outlets and Inlets
American Society of Heating, Refrigerating and Air Conditioning Engineers, Inc
(ASHRAE)
ASHRAE 14 : Methods of testing for rating positive displacement
condensing units
ASHRAE 15 : Safety code for mechanical refrigeration
ASHRAE 20 : Methods of testing for rating remote mechanical-draft
air-cooled refrigerant condensers
ASHRAE 52-76 : Methods of testing Air cleaning Devices used in
general ventilation for removing particular matter
ASHRAE 90A : Energy conservation in new building design (Sections
1 through 9)
ASHRAE 70 : Method of testing for rating the air flow performance
of outlets and inlets
ASHRAE 34 : Number designation and safety classification of
refrigerants
ASHRAE 111 : Practices for measuring, testing and balancing a
building heating, ventilation, air conditioning and
refrigeration systems
ASHRAE : Hand books

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CARRIER : Handbook for air conditioning system design, Carrier

air conditioning company

American Society for Testing and Materials (ASTM)

ASTM A53 : Standard Specification Pipe, Steel, black and hot-
dipped, zinc-coated, welded and seamless
ASTM A90 : Standard Test method for weight of coating on zinc
coated (galvanised iron or steel articles)
ASTM A527 : Standard Specification for steel sheet, zinc-coated
(galvanised) by the Hot-dip process, lock-forming
quality
ASTM A 534 : Preformed, Flexible Elastomeric Cellular Thermal
Insulation in Sheet and Tubular Form.
ASTM A 666 : Standard Specification for Austenitic stainless steel,
sheet, strip, plate and flat bar
ASTM B62 : Standard specification for composition bronze or
ounce metal castings
ASTM B88 : Standard specification for seamless copper water
tube
ASTM B280 : Standard specification for seamless copper tube for
air conditioning and refrigeration field service
ASTM C552 : Standard specification for cellular glass thermal
insulation
ASTM D579 : Standard specification for greige woven glass fabrics
ASTM E477 : Standard Test Method for Measuring Acoustical and
Airflow Performance of Duct Liner Materials and
Prefabricated Silencers.

National Fire Protection Association (NFPA)

NFPA 70 : National Electrical Code
NFPA 90A : Standard for the Installation of Air Conditioning and
Ventilating Systems
NFPA 90B : Installation of warm Air Heating and Air conditioning
Systems.
NFPA 220 : Standard on Types of Building Construction
NFPA 255 : Method of Test of Surface Burning Characteristics of
Building Materials
Rubber Manufacturers Association (RMA)
RMA IP-20 : Specifications for Drives Using Classical Multiple V-
Belts, and Sheaves – Cross Sections, A,B,C and D
Sheet Metal and Air Conditioning Contractors National Association, Inc.
(SMACNA)
SMACNA-06 : HVAC Duct Construction Standards – Metal and
Flexible
Air Diffusion Council (ADC)

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ADC 1062:GRD : Test Codes for Grilles, Registers, and Diffusers

ADC-01 : Directory of ADC Certified Products

Underwriters Laboratories, Inc. (UL)

UL 181 : Factory Made Air Ducts and Connectors
UL 207 : Refrigerant – Containing Components and
Accessories, Nonelectrical
UL 303 : Refrigeration and Air-conditioning Condensing and
Compressor Units
UL 465 : Central Cooling Air Conditioners
UL 555 : Fire Dampers and Ceiling Dampers
UL 723 : Test for surface burning characteristics of building material.
UL 900 : UL Standard for safety air filter units – Sixth Edition
UL 1479 : Fire test of through -Penetration fires stops.

Air Moving and Control Association (AMCA)

AMCA 210 : Laboratory Methods of Testing Fans for rating.
AMCA 300 : Test code for sound rating air moving devices.

AMCA 500 Test Methods for Louvers, Dampers and Shutters.

:
National Electrical Manufacturers Association (NEMA)
NEMA 250 : Enclosures for Electric Equipment (1000 Volts
Maximum)
National Environmental Balancing Bureau (NEBB)
NEBB-01 : Procedural Standards for Testing Adjusting of
Environmental Systems
Associated Air Balance Council (AABC)
National Standards for Field Measurement and Instrumentation, Total
System Balance, Volume
International Electro technical Commission (IEC)
IEC 61260 : Electro acoustics, Octave-band and fractional-octave-
band filters. (Formerly IEC 225)
IEC 60651 : Recommendations for sound-level meters. (Formerly
IEC 651)
IEC 60942 : Electro acoustics, Sound Calibrators. (Formerly IEC
942)
International Organization for Standardization (ISO)
ISO 266 : Acoustics – Preferred frequencies for measurements
ISO 1996 : Acoustics, Description and measurement of
environmental noise

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ISO 9001 : Quality Systems – Model for Quality Assurance in

Design, Development, Production, Installation and
Servicing
ISO 9003 : Quality Systems – Model for Quality Assurance in
final inspection & test
ISO 9004 : Quality Management and Quality System Elements -
Guidelines

2.1.2.3 SIEP / Shell GSI Standards

DEP 31.76.10.10-Gen. : Heating, Ventilation and Air-Conditioning of Plant
Buildings
DEP 31.76.10.11-Gen. : Installation, Testing, Balancing & Commissioning of
HVAC systems.
DEP 33.64.10.10-Gen. : Electrical Engineering Guidelines
DEP 33.65.50.31-Gen. : Static DC Uninterruptible Power Supply (DC UPS)
Units
DEP 80.00.10.10-Gen. : Area Classification (Amendment/supplement to IP
15)
2.1.3 Compliance with Standards
All requirements of this Specification shall apply except where equipment
manufacturers’ standards are more stringent then the latter shall apply.
“Complete installation” shall mean not only the major items of plant and equipment
conveyed by this specification, but all the incidental sundry components necessary for
the complete execution of the works and for the proper operation of the installation,
with their labour charges, whether or not these sundry components are mentioned in
detail in the tender documents issued in connection with the contract.
"As indicated", "where indicated”, and “unless otherwise indicated", refer to items or
requirements which are, or may be given elsewhere in the tender documents issued
in connection with the contract, (e.g. on a drawing, in a supplementary specification or
in a schedule to this specification).
Any deviations from this part of Specification shall be subject to Company approval
and shall be advised in writing to the Custodian.
In all cases, the Company shall determine the adequacy of the design carried out and
Works executed by the Contractor in accordance with this Specification.
2.1.4 Product / Asset Warranty

The entire Works, executed under a particular contract, shall be guaranteed to meet
the specified technical specifications and its referred standards & specifications.
All apparatus shall be built and installed so as to deliver its full rated capacity at the
efficiency for which it was designed and without objectionable noise or vibration (not
more than 2 mm/s). The vibration shall be taken from fan bearing motor end side.
Any defects, identified within the maintenance period as per the contract specified or
a minimum of one year from the date of Provisional Acceptance Certificate, have to
be rectified or replaced by the Contractor at his own cost.
The Contractor shall prepare a repair procedure for the defects. No repair procedures
shall be performed without the prior approval of the Company.

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2.1.5 Quality Assurance and Control

Contractors and Suppliers shall demonstrate to the Principal that they implement
quality control and Assurance systems, which conform to the ISO 9000 series.
All materials used on the project shall be brand new and of high quality. Obtain
approval of all manufacturers from the Consultant and the Company.
"New" is defined as newly manufactured, "state of the art," tested and proven item of
equipment. Items which have been held in stock for any extended period of time by
either the Manufacturer or the Supplier will be rejected.
All materials used on the project shall bear the third party quality assurance stamp
like British Standard kite mark, UL, FM, LPC and/or other quality assurance authority
as stated herein elsewhere.
All materials shall conform to the requirements of the specified British Standards or to
other equipment North American, DIN or European Standards.
2.1.6 Maintenance

Maintenance is defined as the Contractual Liability to maintain the equipment in

working condition, plus the regular checks and servicing of equipment during the
maintenance period to keep the equipment in best working order.
Regular maintenance shall be as necessary, but in any event not less frequently than
monthly.
In the event that the Owner has his own staff, the Contractor is still to check monthly
and advice on any problems and is still to assume responsibility.
2.1.7 Factory Acceptance Test (FAT)
Contractor shall submit FAT procedures and associated documentation for review
and acceptance by Company at least four weeks before planned start of FAT
The following equipment but shall not be limited to “Chiller, Air handling unit,
Condensing unit, Pumps and HVAC control panel” where specified shall be required
for factory inspections, pre-testing, and performance testing at Manufacturer site.
The Contractor shall endure that any deficiencies or shortcomings found during
Factory Acceptance Testing are made good prior to releasing the equipment for
shipment to site.
FAT Procedure

A test plan and procedure should be developed to ensure comprehensiveness of the

test execution. The procedure should, at a minimum, describe the following:
• Define test method(s),
• Define performance test method(s),
• Functionality to be tested,
• Pass/Fail criteria, and
• Test Documentation

The FAT should fully demonstrate that the equipment achieves its specification and
the design basis. As with all testing, the intent is to demonstrate and document that
the equipment operates as intended. The test outcome should give the test team
confidence that the equipment behaves as expected under the full range of
foreseeable conditions, including misuse and error.

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2.1.8 Guarantees

The Contractor will guarantee all material and workmanship for at least one year or as per
project specified, after the issue of final completion certificate issue and take over by the
Company. Compressors shall be under warranty for 5 years for free replacement in case
any defect or failure.
Instruct all Suppliers and Manufacturers that guarantees on equipment will commence
when the completed work is accepted and not from the date the equipment is put into
operation.

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2.2 Scope
2.2.1 General
This specification shall define the minimum requirements for Supply and Installation of
‘HVAC’ Works.
This document shall be read in conjunction with the Company’s General Conditions of
Construction Works and the Contract Specifications. The Contract specifications
contain:
- Scope of Work including Technical Design Parameters
- Particular Specifications
- Technical Schedules
- List of Drawings
Labour, materials, equipment and services to complete the work of the HVAC system
as further specified and as shown on the Drawings;
The manufacture, supply, delivery, erection, testing and adjustment of the complete
heat, ventilation air conditioning system;
All of the material to provide a complete and operational installation to the satisfaction
of the Company incidental component and appurtenance necessary for the proper
operation of the system shall be provided and installed as required whether or not
they were specifically mentioned in the Contract Documents.
This Specification shall define the physical characteristics of the suitable materials
and describes the Works based on product or a method of Specifications. This
Specification shall also define the type of testing requirements and test sheets to be
used.
Plant and non-plant buildings require climatic conditioning (i.e. air conditioning and
ventilation) in order to maintain the temperature, relative humidity and air quality
within defined limits. In this way reliable operation of electronic equipment and human
working conditions are enhanced.
HVAC systems are generally supplied by specialised Manufacturers as package units
or as single components. Standard industrial HVAC equipment should be used.
It shall be ensured that sufficient space in buildings is reserved for HVAC equipment
and its ducting.
Verify location and elevation of all services (Water, Electrical, Telephone, Sanitary,
Storm Drainage, etc.,) before proceeding with the work.
2.2.2 Units of Measurement

Current : Amperes : A
Dimension : metre, millimetre : m, mm
Electrical resistance : Ohms : 

Flow : litres per second : 1/s

Force : Newton : 0.9807 kgf
Frequency : hertz : Hz
Power : watt, kilowatt : W, kW

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Pressure : Pounds per square : PSI

inch
: kPa,
kilopascals (gauge)
Kpa(g)atmospheres : 100 kPa.
bar
Noise : Decibel 'A' scale. : dBA

Refrigeration : Kilowatt : kW

tons of refrigeration : TR = 3.517 kW

Temperature : degrees Celsius : oC

Velocity : metres per second : m/s

Weight : Gram and kilogram : g, kg

Voltage : Volt : V
2.2.3 Shop Drawings

Submit shop drawings and samples for all materials and equipment.
Provide transparencies wherever possible and provide printed copies in a number as
specified elsewhere in the contract documents.
Present a schedule of shop drawings after award of the contract and not later than
what is specified in the contract documents, indicating the anticipated date when the
drawings will be submitted for review. Assume full responsibility for timely submission
of all drawings.
Check for all pertinent information such as physical dimensions, make, performance,
electrical characteristics and indicate the intended use and location before submitting
these drawings. Use reference symbols or enumeration to correspond to the contract
drawings.
Assume responsibility for accuracy of equipment dimensions related to space
available, accessibility for maintenance and service, compliance with inspection
authorities codes. Ensure that shop drawings indicate the shipping and working
weights of all equipment.
The submission of samples will be subject to the same procedure as that of shop
drawings. One set of such samples shall be required to be brought to site and kept
there after approval till substantial completion.
Prepare drawings in conjunction with all trades concerned, showing sleeves and
openings for all passages through structure and all insert sizes and locations.
Prepare composite construction drawings, fully dimensioned, of piping and equipment
in tunnels, shafts, mechanical equipment rooms and areas, and all other critical
locations to avoid a conflict of trades.
Base equipment drawings upon shop drawings and include but do not necessarily
limit to, all details pertaining to access, cleanouts, tappings, sleeves, electrical
connections, drains, location and elevation of pipes, ducts, conduits, etc., obtained
from consultation with, and agreement of, all trades involved.
Prepare drawings of equipment bases, pump pits, anchors, inertia slabs, floor and
roof curbs, wall openings, trenches, pertaining to mechanical work.

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Furnish prints of the reviewed details to all other parties who may require them for
proper coordination of their work, and furnish all information necessary for the work as
a whole.
Obtain Manufacturers' installation directions to aid in the preparation of shop
drawings. Submit two copies of such directions to the Consultant/ Company for his
use.
The Consultant’s/ Company’s review shall not relieve the Contractor from
responsibility for deviations from the Contract documents, unless he has, in writing,
called the Consultant’s /Company’s attention to such deviations at the time of
submission of drawings. The review shall be construed to apply to, and only to,
general arrangements and shall not relieve the Contractor from the entire
responsibility. Any approval by the Consultant/Company shall be on the
understanding that any item submitted shall be ordered with options and
modifications to fully meeting the specification. Any fabrication, erection, setting out or
other work done in advance of receipt of stamped drawings shall be done entirely at
the Contractor's risk and cost.
2.2.4 Protection and Storage
Protect all mechanical & electrical works from damage. Keep all equipment dry and
clean at all times.
Cover all openings in equipment and materials. Cover all temporary openings in ducts
and pipes with polyethylene sheets or caps until final connection is made. The quality
of such cover must be determined with due regard to how long it may be until final
connection.
Be responsible for and make good any damages caused directly or indirectly to any
walls, floors, ceilings, woodwork, brickwork, finishes, services, roads, gardens, etc.
2.2.5 Painting, Colour Coding & Identification

Equipment shall have the manufacturer's standard finish, unless otherwise specified
in the Contract, which, on completion of installation, shall be in good condition or
brought up to original standard.
Ferrous pipe work, brackets, etc. shall be painted with two coats of zinc phosphate
primer. Alternatively, where steelwork is completely enclosed, a proprietary antirust
coating may be used. A finish coat may also be required.

2.2.5.1 PIPEWORK IDENTIFICATION

Pipe work shall be painted in the appropriate colour code in accordance with BS
1710.
All insulated pipe work shall also be colour coded in accordance with BS 1710,
painted full length, adhesive taped or painted with coloured bands.
Primary Identification
Apply colour bands, 300mm wide, white text with green back ground, Pipe labels
should indicate full name of service as “chilled water supply/ chilled water return,
Clearly identify direction of flow in piping with arrows, Arrows shall be mounted to
provide unobstructed visibility from floor level in accordance with BS 1710, to each
pipe at least once in every room or enclosed area; at intervals not exceeding fifteen
metres; at every junction; at every valve; and at every inspection and access position
into service shafts, false ceilings, bulkheads etc.
Colour bands shall not be provided on pipes which are to be painted to match internal
decorations. Where two or more pipes run in parallel, then the colour banding for
each pipe shall be at the same locations.

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At intervals as for colour banding, coloured arrows and wording shall be stencilled to
the insulation or pipe work to indicate direction of flow, and to indicate the circuit or
system.
Secondary Identification
Apply colour bands, 50mm wide, in accordance with BS 1710 and superimpose a
legend identifying circuit, direction of fluid or gas flow, nominal pipe bore and, where
appropriate, fluid or gas pressure.
Colour bands shall not be provided on pipes which are to be painted to match
internal decorations. Directional flow arrows shall be provided on straight pipe
runs, changes of direction and passing through floors and walls.

2.2.5.2 DUCTWORK IDENTIFICATION

Generally colour code and label to HVCA Specification DW 144 (Appendix B).
Primary Identification
Apply colour bands, 300mm wide, to each duct at least once in every room or
enclosed area; at intervals not exceeding ten metres; at every junction; at every
damper; and at every inspection and access position into service shafts, false
ceilings, bulkheads etc.
Secondary Identification
For ducts with longest side or diameter up to and including 225mm. Paint colour
bands 50mm wide and superimpose legends.
For ducts with longest side or diameter over 225mm. Paint or apply transfers to
identification triangles, or triangular plates. Superimpose or incorporate legends.
Triangular Plates
Attach to buckle bands or stool pieces and fix to ducting, with apex indicating
direction of airflow. Submit details of plates and fixings for approval before painting
and marking. Use equilateral triangle of side 150mm minimum.
Legends
Apply transfers of an approved type to colour bands or triangles or triangular plates.
Identify floor and space served, associated equipment reference and direction of
airflow.

2.2.5.3 Plant and Equipment Identification

Each of the plant units and equipment shall be factory painted in accordance with the
manufacturer's recommendations to a colour designated and approved by the
Company. Any damage to finishes which may have occurred during transit, storage,
installation or otherwise shall be made good in the manner recommended by the
manufacturer and to the satisfaction of the Company.
a) Specification plates
Each unit shall have a specification metal plate (the manufacturer's name plate)
which shall show full details as manufacturer's name, unit and unit motors serial
numbers, model numbers, project name, capacities, date of manufacture and BS or
other number for the internationally approvable standard to which the item of plant
conforms.
Specification plates shall be made of stainless steel and should be mechanically
fixed.
b) Water Chiller:

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Full details of water flow rates and design temperatures, condensing and evaporating
temperatures and pressures, refrigerants and lubricants, compressor type and duty,
electrical connections, and any other pertinent information as may be required by the
Company. This plate shall also be securely fixed to each of units local control panel
and protected from the environment influences.
c) Pumps:
Pump size, rpm, amperes, voltage, impeller diameter, lubricants, pump
characteristics, flows for the duty specified, the K factor of the orifice plate if
applicable, and any other pertinent information as may be required by the Company.
This plate shall also be securely fixed to the pump.
d) AHUs, Fan Coils and Fans:
Air flows for the duty specified, fan size, rpm, amperes, voltage, pulley sizes, belt
sizes, air flow, impeller diameter, lubricants, fan characteristics, coil type and
characteristics air and water inlet/outlet temperatures and any other pertinent
information as may be required by the Company. This plate shall also be securely
fixed to the fan. An engraved label shall be fixed to each filter stating the maximum
permissible pressure drop.
The same as above is applicable to any other single piece of equipment or units
within the HVAC systems.
e) Identification plates
In addition to the specification plates, each unit shall be provided with an identification
plate showing the code number for each unit as indicated on the system schematics.
This plate shall be securely fixed to the unit in a prominent position.
f) Valve Equipment Labels
Valves shall be clearly labelled, and colour coded in accordance with BS 1710.
Labels shall be 100 mm x 40 mm, Colour/Black/Colour, multi-layer laminated plastic
both sides, showing the tag number and the service. Labels shall be attached to
valve spindles using short lengths of chain.
A valve chart, indicating both duty and position of all valves, shall be provided, in a
glazed picture frame and located as approved by the Company. Copies shall be
included as part of the As-Built Drawings.
Equipment shall be clearly labelled to identify equipment tag number and/or
equipment name and service. Labels shall multi-layer, White on Black, laminated
plastic, front-engraved and securely fixed to equipment by stainless steel screws or
blind rivets.
2.2.6 Test Points & Instruments
Test points shall be provided as required for commissioning, whether shown on the
Contract Drawings or not, generally as given below to allow in-operation temperature
and/or pressure readings.

2.2.6.1 Test Points & Instruments for Pipe Works

Pressure and temperature test points in pipe work systems shall be provided at all
main branches and on flow and return connection to all cooling coils, and on all
connections to 3-way valves.
Temperature test points for pipe work shall comprise a 100 mm long x 15 mm brass
diameter well or sealable measuring nipple.
Thermometers for pipe work shall be bi-metallic type with a 100 mm dial, black case,
chrome bezel, 100 mm long stem and 15 mm BSPT connections, calibrated in °C.

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Pressure test points for pipe work shall comprise a 10 mm diameter female brass
gauge cock and brass plug or sealable measuring nipple.
Pressure gauges for pipe work shall be the Bourdon type with a 100 mm diameter,
black case, chrome bezel and 10 mm BSPT connection, calibrated in PSI.

2.2.6.2 Test Points & Instruments for Ductwork

Pressure and temperature test points in ductwork systems shall be provided before
and after all air handling units, cooling coils and at fresh air and re-circulation inlets,
whether shown on the Contract Drawings or not.
Pressure and temperature test points for ductwork shall be 25 mm diameter holes
provided with an effective seal.
Test plug for AHU shall be to suit the panel thickness, by adding a further nut at the
lower thread end the plug can also be used on insulated ducting. Plug body cap and
nuts are made of brass. Cap seal neoprene and strap ethylene propylene rubber.
Thermometers for ductwork shall be bimetallic type with a 100 mm dial, black case,
chrome bezel, 300 mm long stem and calibrated in °C.
Pressure gauges for ductwork shall be diaphragm-actuated type with a 100 mm dial,
black case and bezel and 3 mm BSPT connections, calibrated in PSI.
2.2.7 Commissioning & Handover
This section of the document provides guidelines for planning, responsibility,
resources and documentation for commissioning system by system. Technical
commissioning requirements for each service are given in the relevant Parts of these
Specifications.
The commissioning period should comprise the following activities and events.
- Pre-commissioning.
- Commissioning and Start up.
- Contractor Substantial Completion.
- Contractor Completion.
- Handover to Asset Custodian.
A standard Contract Completion & Handover pro-forma is included in Appendix B of
this document.
Commissioning & Handover Procedure
A comprehensive method statement for Pre-commissioning and Commissioning the
Works shall be submitted to the Company for approval, well in advance of the
planned start.
The Method Statement shall include, but not be limited to:
- Identification of all systems
- Details of tests and demonstrations
- Samples of documentation (check lists, test sheets, test reports etc.)
- Details of test instruments

2.2.7.1 Commissioning Programme

A Commissioning Programme shall be submitted to the Company for approval at the
same time as the Method Statement.

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The Commissioning Programme should be appropriate to the size and complexity of

the project, and should contain a network of activities sufficiently defined to indicate
the following milestones for each system.
- Pre-commissioning completion.
- Commissioning completion.
- Substantial Completion
- Handover.
The Commissioning Programme should include:
- Step by step procedures.
- Planning and resources.
- Details of specialist requirements.

2.2.7.2 Pre-Commissioning
Before pre-commissioning starts, the updated drawings, manuals, certificates and
factory test data shall be made available.
Materials, instruments and equipment shall be provided as required to carry out the
tests adequately, efficiently and safely. Test instrument calibration shall be checked
before use.
Before commencing work, verify that systems are complete and operable. Ensure the
following:
a. Equipment is operable and in a safe and normal condition.
b. Temperature control systems are installed complete and operable.
c. Proper thermal overload protection is in place for electrical equipment.
d. Filters are clean and in place. If required, install temporary media in addition to final
filters.
e. Hydraulic systems have been flushed, filled, and vented.
f. Pump motors have been checked to verify rotation is correct.
g. Proper strainer baskets are clean and in place.
h. Service and balance valves are open.
I. Fan motors have been checked to verify rotation is correct.
j. Fire and volume dampers are in place and open.
k. Duct system leakage has been minimized.
l. Coil fins have been cleaned and combed.
m. Access doors are closed, and duct end caps are in place.
n. Air outlets are installed and connected.
o. Fans and motors have been lubricated.
p. Alignment of pulleys and belt tension has been adjusted on each fan.
q. Fire, volume, and splitter dampers are operable and linkages are lubricated.
r. Position indicators are visible.
s. Field mounted gauges are installed and calibrated.
t. Confirm operation of ESD (Emergency Shutdown System).

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u. Identify all duct traverse locations on the as-built drawings. Number and identify
each on the drawing and in the field.
v. Check whether indications in DCS (digital control system) are available.
w. Check the running and standby units are operating.
2.2.8 Testing, Adjusting & Balancing
DEFINITIONS
Systems testing, adjusting, and balancing is the process of checking and adjusting all
the building environmental systems to produce the design objective. It includes:
The balance of air and water distribution, adjustment of total system to provide design
quantities, electrical measurement; verification of performance of all equipment and
automatic control; sound and vibration measurement.
Test: To determine quantitative performance of equipment.
Adjust: To regulate the specified fluid flow rate and air pattern at the terminal
equipment (e.g. reduce fan speed, throttling)
Balance: To proportion flows within the distribution system (sub-mains, branches,
and terminals) according to specified design quantities.
Procedure: Standardized approach and execution or sequence or work operations to
yield reproducible results.
Report forms: Test sheets arranged for collecting test data in logical order for
submission and review. These data should also form the permanent record to be
used as the basis for required future testing, adjusting, and balancing.
Terminal: The point where the controlled fluid enters or leaves the distribution system.
These are supply inlets on water terminals, return outlets on water terminals, and
exhaust or return inlets on air terminals such as registers, grilles, diffusers, louvers
and hoods.
Main: Duct or pipe containing part of the system’s capacity and serving two or more
branch mains.
Branch main: Duct or pipe serving two or more terminals.
Branch: Duct or pipe serving a single terminal.
When satisfied that a system, or systems, complies with the Contract Documents, the
Contractor shall give the Company adequate notice, in writing, that it is ready for test
and demonstration.
If full load conditions are not available, a system may be commissioned on part load.
The Contractor shall, however, repeat the tests and demonstrations under full load
conditions at such time(s) as it may be possible to do so.
The Contractor shall finally demonstrate to the Company that all systems of the
installation, already commissioned separately, operate simultaneously in accordance
with the Contract Documents.
Requirements include measurement and establishment of the fluid quantities of the
mechanical systems as required meeting design specifications and recording and
reporting the results.
Test adjusts and balances the following mechanical systems:
Supply air systems, all pressure ranges, including variable volume system
Return air system
Exhaust air system

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Noise and sound control

Water piping system
Control system
2.2.9 Test Report & Documentation Format

Documentation should be used in the formats given in the Appendices to these

Specifications. When no suitable format is available, documentation shall be subject
to Company approval.
Copies of all completed Pre-commissioning and Commissioning documents
witnessed and approved by the Company, shall be included in the Operation and
Maintenance Manuals.
2.2.10 Spares, As-Built & Manual

2.2.10.1 Maintenance Tools

Such special tools as are required for testing or dismantling and assembling items of
equipment shall be provided in each equipment room.
In addition, 2 no of keys for the operation of each size of lock-shield regulating valve,
air cock, automatic air valve or other valve requiring special tools to operate, as well
as duplicate keys for any clockwork mechanism, locks, instruments or safety
equipment shall be provided.
Spare Parts
Classification Description
Initial Spares Spares required for Commissioning and First Year
operation.
Subsequent Spares required after First Year operation.
Spares
Insurance Spares High cost items held in store as insurance against
breakdown, not including spare parts used in normal
maintenance programmes.
Procurement
Initial & Within 6 weeks of each material approval, the Contractor
Subsequent shall provide manufacturer’s lists of the recommended parts
Spares to be held. The list should be completed on Company
Spare Parts List and Interchange ability Record forms
(SPIR). The company shall select from these lists and
procure and store the necessary items.
Insurance Shall be identified in the Particular Specification Spares for
each project. The Contractor shall supply these items prior
to Substantial Completion.

2.2.10.2 As Built Drawings

As Built Drawings shall be prepared, coordinated and submitted to the Company for
approval prior to the issue of the Substantial Completion Certificate. As Built
Drawings shall have the words ‘AS-BUILT DRAWING’ clearly indicated adjacent to
the title block.
As Built Drawings shall include but not be limited to:
- External layout drawings at 1:500 or 1:100 scales.
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- General arrangement drawings to a scale of 1:50.

- Detailed layouts of all plant and equipment areas, motor rooms, switch rooms,
etc, at a scale of 1:20.
- Control and protection drawings, diagrams and schematics.
- Schedules of equipment.
- Mounted Block Plans showing fire zones.
In addition, the Contractor shall provide 3 sets of manufacturers detail drawings of all
motors, switchgear, internal wiring, etc., as appropriate.
The above drawings and schedules shall be specially prepared for record purposes
and shall be submitted to the Company as 3 sets of dyeline prints, to be bound into
the Operation & Maintenance Manuals, and one set of electronic copy, unless
specified otherwise in the Contract Documents.

2.2.10.3 Operating & Maintenance Manuals

Operation & Maintenance Manuals shall be prepared, coordinated and submitted to
the Company for approval prior to the issue of the Substantial Completion Certificate.
Operation & Maintenance Manuals shall include, but not be limited to:
- An index.
- A full description of the services.
- Illustrations describing operational routeing together with line diagrams
showing the location and function of controls and valves.
- Maintenance routines and details of spare parts
- Original, not photocopy, manufacturers details of all equipment with
maintenance and operating instructions.
- Emergency measures and telephone numbers of Vendors, Installers,
Manufacturer, etc.
- Safety Procedures necessary for the proper operation and maintenance of
the installation and equipment.
- As Built Drawings.
- Commissioning and Testing Records and Reports.
Operation & Maintenance Manuals shall comprise 3 nos. securely bound copies of
each, unless specified otherwise in the Contract Documents.

2.2.10.4 Training
The Contractor shall be responsible to train adequate number of Operators or
Maintenance Staff deputed by the Company. They shall be trained for correct
operation, safety devices, control and maintenance of all air conditioning services
provided under the contract before the works are handed over to the Company. 'The
training shall be carried out by the qualified commissioning staff of the Contractor, for
each particular service and shall continue till the operators or maintenance staffs are
fully conversant with all aspects of operations.

2.2.10.5 Coordination with Other Division

Particular attention must be paid to the proximity of electrical conduit and cable to
mechanical piping and equipment. Electrical conduits shall not touch or be supported
on pipe or duct.

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Confer with all trades installing equipment which may affect the work of this division,
and arrange equipment in proper relation with that equipment installed under all
Divisions of the Contract.
Furnish all items to be built in by others, in time, complete with all pertinent
information, commensurate with the progress of the work.

2.2.10.6 Existing Service and Equipment

All changes and connections to existing services shall be made only in a manner and
at a time approved by the Company, so as to avoid any interruption of such services
during normal working hours. If necessary, changes and connections to existing
services shall be made outside of normal working hours, at no extra cost.

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2.3 Air-Conditioning & Ventilation Design General Specification

2.3.1 General
The Building Services design shall include, but not be limited to, overall scheme design,
sizing of equipment, duct & pipe work and coordination with other service.
HVAC system shall be designed to provide temperature, air quality and humidity
controlled environments for personnel and equipment in accordance with design criteria
given in this document. The design of the system should cater for the adverse desert
environments with fine sand and occasional high humid conditions. Systems shall
incorporate the use of filtration, cooling, heating and humidification/ dehumidification as
required meeting this objective.
Detailed design shall be prepared using established design methods, as given in
ASHRAE Fundamentals Handbook. Loads should be calculated using ASHRAE, Carrier
or CIBSE methods.
HVAC design review shall be carried out during details design stage
The heat load calculation shall be carried out using the latest version of Carrier HAP
programme only.
The air conditioning system shall provide comfort conditions in all rooms throughout the
operating period.
Cooling loads shall be calculated with maximum summer design dry Bulb Temperature
and mean coincident wet Bulb temperatures.
Overall building heating and cooling loads shall be calculated. Zoning, exposure, and
building mass shall be considered in heating and cooling load calculations. The heating
requirements for the winter conditions shall be based on zero internal heat gain.
Each zone, room and portion of a room with a different load profile, orientation and
sensible and latent load shall be calculated. A separate block load for each air handling
system shall be calculated.
The cooling load calculations shall be considering the following.
(I) Solar heat gain from glass, wall, and roof. Solar loads shall be based on maximum
instantaneous values in appropriate direction for consideration of the worst exposure
calculations.
(II) Transmission heat gain from glass, partition, ceiling, floor and infiltration.
(III) Internal heat gain from people, equipment, lights, appliances
(IV) Ventilation heat loads.
Actual U factors shall be calculated based on Architectural drawings.

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The HVAC system shall be selected as follow:

- If the building is not serving Hydrocarbon facility then the table 1 shall be used.

Table 1:

Building without battery Building with battery Requirements

room room
(Group A)
(Group B)
Heavy duty free Same as Group A but the -The units shall be
standing(HDFS) units shall battery room shall be feed uniformly distributed in
be used with 20% standby from fresh air system the space.
units (e.g. if the building consisting of Condensing
- The units (HDFS) shall
required 10 working units unit and Air Handling Unit
be top discharge.
than two more additional or heavy duty package unit
- The units(HDFS) shall
units shall be provided as to feed the battery room
not be used inside the
standby) with operation and providing positive
battery room
sequence controller pressure for other area
- The operation sequence
shall be changed in
weekly basis including the
standby units

Package units with duty Heavy duty package units Supply and return duct can
and standby(100% with duty and be common between the
capacity) arrangement standby(100% capacity) units or each unit can be
arrangement ducted separately

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- If the building is serving the hydrocarbon facility then table 2 shall be used.

Table 2:
Building with and without Building with battery Requirements
battery room room
(Group C)* (Group D)*
Condensing unit and Air Condensing unit and With all associated
Handling Unit Air Handling Unit facilities e.g. duct
work, control system ...
Group
Chilled water system Chilled water system With all associated
facilities e.g. duct
work, control system,
chemical dosing,
pressurisation unit ...
Package units with duty and Any of the above **This system may be
standby arrangement for used with following
telecom building** condition:
- if there is no
separate
battery room
- if the load is
not more than
60 Ton

*During the FEED or details design of the project, the project team shall be submitting all
necessary data to technical safety (MSE4) in order to evaluate the necessity of the ventilation
requirement for the building(s).

Building pressurization: All hydrocarbon facilities Buildings shall be pressurized by

minimum 30 Pascal. The outside air available for pressurization shall be the difference
between the total air supply and total exhaust air from the pressurized space.
All motorized dampers, gas detectors, sensors and HVAC Direct Digital Controllers
(DDC) relevant to the operation of the pressurization system shall be feed from the
uninterruptible power supply (UPS), or have an independent emergency power
supply in addition to the normal power supply.
For all pressurized buildings a differential pressure sensor (digital type with LCD
screen to show the differential pressure in PSI) shall be installed for measuring the
static pressure difference between the interior and exterior of the building. The
external static pressure (atmospheric) shall be configured in the HVAC control panel.
Pressure sensor shall be linked with DDC for command and status signal. Each room
shall be equipped with its own sensor. The location of the sensor for each room shall
be decided during HVAC design review or details design stage.
Specialised manufactures generally supply HVAC systems as package units or as
single components. Standard HVAC equipment, suitable for the prevailing conditions,
shall be applied as for as possible. The design of HVAC system may specify Chilled
water system, VRF/VRV system or Direct expansion system. The HVAC design
philosophy for the building must address the suitability and economics of the selected
system.
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Direct Expansion unit is a unit consisting of a compressor and a condenser. The

refrigerant vapour is compressed to a certain pressure, condensed to liquid refrigerant
and then vaporised, thus utilising the vaporising refrigerant's latent heat in a cooling. The
vaporised refrigerant is returned from the coil to the compressor.
The Refrigerants shall have zero ozone depletion refrigerants and less global warming
potential (GWP).Weight-age shall be given for refrigerants which have complied to less
GWP.
District chilled water service installations should comprise buried mains served from a
chiller compound suitably located to reduce the environmental impact, particularly noise,
on adjacent buildings. The chiller compound pump room may be combined with an
electrical substation in one building. Allowance should be made for future expansion of
district chilled water schemes, and this should be done with minimal costs. For schemes
with a high probability of future expansion, ring main chilled water distribution is
provided, with secondary chilled water pumps at each building. For other schemes,
radial distribution may be appropriate. In any case, the logistic and limits of future
expansion should be established and agreed with the Company.
All HVAC systems covered by this specification shall be provided with standby units with
100% capacity. HVAC control panel (microprocessor based) shall alternatively operate
the working and stand by units on weekly basis. This will distribute uniformly the wear
and tear.
Fresh air intake duct shall be provided with motorized dampers or as project specified.
H2S or flammable gases detector shall install in the fresh air intake duct, In case of gas
detection. High integrity, low leakage “damper shall be installed in the fresh air intake as
per EN 1751 class 3, ~40 litres/sec for a 1m² damper at 2000 Pa DP. Also volume
control damper shall be provided in the fresh air duct. The high integrity damper shall be
provided with actuator in order to close the damper within two seconds as maximum.
Sand trap louver shall be provided in fresh air intake duct and louver shall be sized on
1.5m/s velocity for economically and efficiently.
Building Automation System shall be considered when specified, for evaluating,
controlling the HVAC system from a centralized location, the integration of HVAC control
systems and the Building Automation System shall be considered on project basis.
A separate toilet/locker exhaust system shall be provided in all cases where these
facilities are provided and shall in no case be clubbed with exhaust of other areas. All
exhaust fans shall be provided with thermistor to protect from overheating.
Outside air intakes shall be designed to be taken to higher elevation to avoid the
potential of introducing any hazardous gas, dust or chemicals into the building.
All necessary fire/smoke dampers shall be provided within the air conditioned ducts,
return and exhaust openings penetrating and/or passing through walls and fire zones.
All equipment, ducts, pipes, controls, etc shall be fully treated against corrosion and
sealed against moisture, sand and dust ingress.
Air handling unit: Air handling units shall be draw-through type except in instances
where noise criteria requirements can best be met by using blow through units. Access
doors shall be provided in each section of air handling units. Recirculation Units shall
include, when necessary, a mixing box section, with outdoor air and return air dampers
for mixing of the return and outside air, filters, cooling coil, supply fan, and steam
humidifier. The AHU shall be housed inside a room with air conditioning. Rooftop
locations are acceptable, if space availability is a concern but with proper accessibility to
the roof e.g. concrete stair case. Also proper maintenance methodology is maintained. If
the AHU shall be located in the roof due to the non availability of the space in the ground
then the following condition shall be applied:
Minimum space of 1.5 meter shall be maintained all the way around each unit.

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Safe access to be provided to reach the unit and its accessories e.g. proper bridging
with hand rail.
To protect people falling from the roof, the height of parapet wall adjusted to the units
shall not be less than 1.5 meters or normal height of parapet wall can be maintained
with extended protection height by other means such has handrails.
Providing dog house in case of slab cut-out or/and side wall entry in case wall cut-out
as per the sketches provided in this SP.
Provide duct support all around the duct if the height of the duct is more than one
meter from floor finish level of the roof.
Water tank (1200 gallons) with two taps (one for AHU area and the second one for
the DX/chilled system) shall be provided for maintenance of the HVAC. Also power
out let shall be provided for both locations (as above).
The following paragraphs describe general requirements of the air handling unit
components. For specific material and construction requirements, see Section-3
Duty/stand by air handling units shall be fitted with shutoff dampers (motorised
damper) to allow maintenance of the stand by unit when the other unit is running.
b) Filters: Access sections with doors shall be provided at each filter section as
required for the maintenance, filter cleaning and replacement.
Fresh air ventilation units for control buildings, Computer buildings & auxiliary rooms
shall be provided with a pre-filter for 85% efficiency ASHRAE dust spot and an after-
filter for 92% efficiency ASHRAE dust spot (dust spot tests according to
ANSI/ASHRAE 52.1). For other buildings, after-filter efficiency shall be not less than
80 %.
A dust collector shall be applied if the dust concentration at the fresh air intake is
more than 10 mg/m³.
Re-circulation air handling units shall be provided with 85% efficiency ASHRAE dust
spot test filters.
c) Cooling coils: Cooling coils shall be located within the air handling units and shall
be sized and arranged for maximum water velocities of 2.4 m/s. Cooling coil shall be
designed to have maximum air face velocities 2.5m/s to prevent moisture carry over.
Cooling coil performance shall be rated in accordance with ARI 410.
d) Heating: Heating shall be provided by electric heaters. Heater shall be located
within the system supply branch ductwork and/ or in air handling unit (when
necessary). Heater shall be U.L. listed for the appropriate service. Electric heater
shall be suitable for area classification.
e) Supply fan: Supply fans shall be centrifugal type, backwardly inclined and air foil
blades. Fans shall be tested and rated in accordance with ASHARE standard 51 and
AMCA 210. Fans shall be AMCA tested, certified and labelled. Fan and housing
assemblies shall be isolated from vibration and insulated as required to maintain a
maximum sound power level rating of the unit at 85 dB, in accordance with AMCA
standard 301.
f) Motors: In general, all HVAC equipment motor shall be the high efficiency type.
See electrical specification for electrical items on package equipment, for motor
criteria. Terminal box for motor cable shall be provided in the AHU wall close to fan
section and from the box to the motor the cable shall run through closed cable tray.

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g) Ventilation: Ventilation air shall be brought in from the outside through intake air
louvers in the exterior building walls, designed to prevent penetration of sand and
moisture. Louvers shall be specially designed to prevent sand penetration during sand
storms. All intake air ducts shall be provided with gas detection devices, to be used for
the detection of hydrogen sulphide (when necessary).
All Fresh air intakes shall be provided with H2S (for sour projects) and flammable gas
detectors (or any other type of detector specify in the project document). Motorised
dampers shall be provided at all air inlets and outlets. Motorized damper with zero time
response shall be provide at inlet of fresh air, if specify in the contract.
h) Outside air requirements: outside air ventilation rates shall be provided in
accordance with latest revision ASHARE standard 62.1 and as given in appendix-B of
this specification whichever greater.
I) Relief air: Relief of air shall be accomplished with gravity operated relief air dampers.
These dampers shall be set to relieve at specified building pressurization requirements.
This damper shall be start to open at +12pa (0.05 in wg.) above the mentioned pressure.
j) Exhaust: Exhaust shall be provided for rest room, photocopy machine room, toilets,
kitchen, battery room, laboratories, and similar areas (when applicable) as indicated in
appendix –B and in ASHRAE standard 62.1. Air shall be exhausted by dedicated
exhaust fans. Fans shall be accordance with fan specification. Exhaust outlets shall be
located away from all air intakes. Exhaust rates shall meet minimum criteria as given in
ASHRAE standard 62.1 and as given in appendix-B of this specification. Exact required
exhaust rates shall be determined from detailed design calculations.
k) Chillers: Design criteria: The HVAC chiller system shall be designed to provide
chilled water to air handling system used for space cooling. The chiller shall be located
outdoors. Chiller shall be air cooled/water cooled, electric driven, with compressors.
Chiller shall be capable of capacity modulation. Capacity modulation shall be based on
leaving water temperature. Reciprocating chiller shall be provided with hot gas by pass
to allow a more stable leaving water temperature at light load conditions.
The chiller shall be a microprocessor based control unit. All controls and motor starting
equipment shall be factory wired and mounted in a weather-proof enclosure. Chiller shall
be accordance with chiller specification in Section- 3.
l) Condensate Drains: Condensate drains from indoor terminal units should discharge
to nearest soak way. The drain line shall be provided with open-able trap with water seal,
cover with insulation and metal cladding.
m) Refrigerant Pipe work: Pipe work shall not be directly buried, not chased in floors or
walls, but shall be enclosed in preformed ducts or voids. Refrigerant pipes shall be
insulated as per given specification in section-3 with metal cladding and run in a metal
tray.
n) Automatic Shutdown: The HVAC controls shall be interlocked with the fire and gas
detection system. Activation of a fire alarm shall cause the shutdown of air conditioning
system, unless continued operation of the system does not cause spread of smoke to
outside the area where the fire has been detected. In case of detection of H2S,
Hydrocarbon or any flammable gases, the fresh air intake motorized damper of air-
conditioning system shall shutdown automatically to prevent ingress of gases into the
building through fresh air system and air conditioning system shall be shutdown.
o) Legionnaires Disease: Where installations include evaporate water-cooling, the
guidelines of CIBSE TM 13, minimising the risk of Legionnaires disease, shall be
followed.
Particular attention is drawn to the optimum temperature for multiplication of bacteria and
to the design, operation and maintenance of evaporative water-cooling system.

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2.3.2 Design Criteria for Air Conditioning & Ventilation Works

2.3.2.1 Outdoor Conditions

Design outdoor conditions should be based on relevant meteorological data for each project
area and shall be subject to Company approval. In the absence of definitive data, the figures
given in Table -3 shall be used.
Table -3: Outdoor Air conditioning Design Criteria.

Location Summer Winter

Coastal Oman 48/32 0C DB/WB 18/15 0C DB/WB

North Oman 52/32 0C DB/WB 12/11 0C DB/WB
South Oman 50/32 0C DB/WB 12/10 0C DB/WB

2.3.2.2 Indoor Conditions

Refer to Appendix-B includes the following criteria relating to the majority of company
facilities.
- Room temperature
- Room humidity
- Minimum fresh air
- Minimum air change
- Maximum noise rating
Where criteria are not listed in Appendix-B, design indoor conditions should be based
on the ASHRAE standard new edition, CIBSE Guide, Section A1, Environmental
Criteria for Design, and shall be subject to Company approval.
Contractor to use actual equipment heat gains from the selected equipment in the
calculation.
Humidity shall be necessary control. However, the critical psychometrics of each
design should be checked to ensure that reasonable comfort conditions are always
achieved.

2.3.2.3 Chilled Water distribution System:

The chilled water system will include but not be limited to the following items. The
chilled water system comprising chiller, chilled water circulation pump, air handling
units, chemical dossers, feed and expansion pressurization units, chilled water pipe
work, control and accessories.
Design criteria: Chilled water shall be distributed from chiller to air handling systems
located in the buildings. The chilled water distribution system shall be constant
volume or variable volume type.
Chilled water piping system shall be designed by the following:
Piping shall be sized based on a maximum flowing water pressure drop 39 kpa
per100 meter (4ft/100ft). Water velocity shall also be considered in pipe sizing. In
general, piping 50 mm diameter and smaller shall be designed for a water velocity 1.2
m/s. Larger piping shall be sized based on pressure drop, but at no time shall the
velocity in any size pipe exceed 2.5 m/s.

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2.3.2.4 Air distribution system:

Air distribution systems shall be designed to supply, return, and exhaust air as
required to provide an indoor environment suitable for personnel and the equipment
located within. Air distribution systems shall be designed in keeping with industry
standards, and in accordance with all applicable SMACNA publications, and DW 144.
Air distribution systems shall conform to the following criteria.
Duct Work: Rigid and flexible ductwork shall be constructed in accordance with the
latest edition of SMACNA “HVAC Duct Construction standards”. Ductwork shall be
sized based on the static regain / equal friction / velocity reduction. Ductwork shall be
designed to minimize noise transmission and to avoid noise generation from the
components or fittings.
Ductwork air velocities shall not exceed the following limits:
For Air handling unit/Main duct Maximum velocity = 11-12 m/s
Maximum pressure drop = 0.60Pa/M.

For Fan Coil units/ Main duct Maximum velocity = 4.50 m/s
Maximum pressure drop = 0.40Pa/M

For Central Extract Fans/ Fresh Air Maximum velocity = 9.10 m/s
Units. Maximum pressure drop = 0.80Pa/M

The above limits may be exceeded in areas where space restrictions exist; it’s subject
to approval from the company.
In general, ductwork shall be constructed of galvanized sheet metal with flanges,
seams, supports, etc., to match the appropriate duct classification as defined by
SMACNA/DW 144 unless moisture in the system dictates the use of aluminium or
stainless steel materials. Flexible duct shall be a maximum of 1 meter in length.
All rectangular 45 to 90 degree elbows ductwork shall contain turning vanes. Kitchen
exhaust ductwork shall be welded stainless steel. See NFPA 96 for kitchen exhaust
ductwork design restrictions.
Balancing devices shall be provided at each supply branch connection. Balancing
devices shall also be provided at return air and exhaust air devices to obtain required
return and exhaust airflow. Pressure loss for each outlet on each ductwork branch or
run shall be approximately equal to ensure uniform air distribution.
Quick selection of air terminals shall be carried out based on a face velocity of 2.5
m/s (500- FPM). Similarly, air intake louvers shall be sized on a face velocity of 1.5
m/s (300 FPM) and extract air louvers on a face velocity of 2m/s (400 FPM). Face
areas shall be gross area and not net free area.
Maximum noise criteria shall be as given in appendix –B of this specification.
All inlets in finished spaces shall be installed with an inlet air boot for appearance and
noise control. Air inlet/return devices should have volume control dampers.
Pressure sensor shall be installed in supply duct and link with the DDC to monitor the
duct pressure.
The Air-Conditioning & Ventilation system, materials and Equipment shall comply with
the section-3.

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2.3.2.5 Equipment Overcapacity

The HVAC load calculations shall include an overall excess capacity- in the total of
heat load calculation- of 15%, as an ageing factor.
It shall also take into account capacity de-rating due to high ambient conditions, de-
rating shall not be more than 20% at 55 °C.
The percentage of future safety factor shall be decided by individual project
specification if it is required.
Vendor shall furnish de-rating factor for the offered unit and substantiate it with
supporting performance sheets.

2.3.2.6 Coefficient of performance

Air conditioning equipment shall be selected aiming for the highest operation
efficiency. The minimum Coefficient of Performance (COP) at 48°C for all Air
Conditioner shall be 2.2(integrated) for all types of compressors.

2.3.2.7 Selection of Equipment

Selection of equipment shall be based on this General Specification, the Particular

Specification, and the technical data contained in the Drawings for a particular
installation.

Where items of equipment are interconnected to form an integral part of the complete
air conditioning installation, their characteristics of performance and capacities shall
be so matched as to give safe, reliable, efficient and economical operation of the
complete air conditioning installation.

2.3.2.8 Air Recirculation Limitations

Air recirculation shall not be permitted from the following areas:

· Hazardous classified areas and/or areas classified for dust;
· Battery rooms;
· Chemical storages;
· Laboratories;
· Toilets;
· Locker rooms;
· Janitor rooms;
· Printing rooms or photocopy rooms;
· Pantry rooms, tea rooms, kitchens and alike;
-Canteens and cafeterias (except that air may be re-circulated where the air handling system
serves only spaces of the same air class according to ASHRAE Standard 62.1);
· Garages;
· Painting shops;
· Any other area required by ASHRAE Standard 62.1 and/or by applicable health and safety
regulations.

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2.4 Specialist Areas

2.4.1 Battery Rooms

Battery rooms shall be air-conditioned to maintain a maximum temperature of 24oC
with minimum of 6 ACH. If battery temperature (24oC or less) can’t be achieved by 6
ACH then ACH shall be increased in order to maintain the battery room temperature.
The air from battery rooms shall not be recycled.
The ventilation air in room shall be through dropper(s), the dropper shall not be higher
than 300 mm above the finish floor level. One dropper shall be provided in between
every battery racks. The dropper shall be made of G.I with insulation as per duct
insulation specification and with metal cladding. Motorised damper shall be provide in
main supply duct of room and shall be linked with the DDC, if motorised damper
installed inside the battery room it shall be explosion proof otherwise it shall be
normal type. Each dropper shall be provided with VCD for proper control of air. The
VCD shall be located 2.5 meter from floor finishing level.
The HVAC supply duct droppers shall throw air between the battery rows and direct
hit of the battery rocks is not allowed.
The explosion proof extract fan(s) working and stand by shall be provided in the
opposite direction of the droppers, if not due to any technical reason then ducted
explosion proof exhaust fan shall be used. Air inlets and outlets shall be located to
provide effective cross ventilation over the batteries.
No false ceiling is allowed in battery rooms. Pockets for collection of flammable gas
within battery room ceiling shall be avoided. However, if not possible, then means
shall be provided to withdraw any collected flammable gas from the highest within this
ceiling pocket. The battery room shall be maintained at a negative pressure relative to
adjacent spaces and positive pressure of 20 pa relative to atmosphere. Differential
pressure sensor (digital type) shall be installed to monitor the battery room positive
pressure. The sensor shall be provided with LCD screen and shall be explosion proof
type suitable for zone 1class 2B and T4.

2.4.2 Control Rooms and Field Auxiliary Rooms

Control buildings contain vital electronic equipment.
A ducted air conditioning system shall be provided maintaining the control building
under positive pressure +30 pa to reduce ingress of dust.
Provide a separate thermostat to control the temperature of this room and Maintained
an internal temperature as per appendix-B.
Humidity control shall be provided by the air handling units cooling coils. Provision
shall be made to allow the condensate to discharge into nearest drain point.
Air-handling and condensing units shall be located in an external enclosure.
Account should be taken of possible future expansion of the building.

2.4.3 Electrical Substations & Switch Houses

Substations and switch houses should normally be designed as completely closed
structures, with dust tight construction and cable passages.
The air conditioning design shall include two separate installations, which shall be
individually electrically supplied and controlled.
The indoor design criteria shall be such that:

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HVAC system and equipment selection for the buildings will be capable of producing
a positive pressure 30 pa in the rooms, the positive pressure will minimise the dust
ingress from outside.
During normal operation, the maximum indoor temperature shall not rise above 24 oC
DB. The maximum supply air relative humidity shall not exceed 60%.

2.4.4 Gas Bottle Stores

Spare and empty gas bottles shall be separated and stored in an upright-chained
position and housed in a purpose built, well-ventilated, shaded and secured
enclosure located at least 20 m from combustible materials. Possible air pockets at
high level shall be avoided.
Requirements are normally satisfied by the provisions of a cage of tubular frame,
chain link fencing and roof sheeting with an internal separation.
Electrical installations in gas bottle stores shall be suitable for Zone 2.

2.4.5 Kitchens
The guidelines given below address commercial catering installations, criteria for
domestic kitchens are given in Appendix-B.
Often it is not possible to achieve comfort conditions in kitchen cooking areas at all
times because of the extremely high expenditure involved. In such cases, it should
be sufficient to maintain acceptable working conditions with maximum of 24°C with
70% RH.
Generally air should be extracted from cooking and subsidiary areas through
stainless steel double-skin hoods, minimum sheet thickness 18 gauge located over
the main cooking, Chapatti area, Bakery/Pastry and dishwashing equipment. Hoods
should be sized to overlap equipment by 150 mm each side, to have a minimum face
velocity of 0.3 m/s and to have a minimum clearance of 1900 mm above finished floor
level. Vertical distance from lower lip of the hood and the cooking surface shall not
exceed 1200 mm. The hood volume should suit the equipment covered. 80 – 85% of
the replacement air should be provided, as treated (cooled and filtered) outside air
with 85% efficiency, at the internal perimeter of the hood. If this part of the
replacement air is supplied outside the hood, it should be 100% outside air-cooled to
plenum conditions. Ducted, re-circulating systems should not be used because of
greasing problems. The remainder of the replacement air should be drawn from
adjacent areas so that a negative kitchen pressure is maintained to contain odours
but Kitchen pressure shall be maintained positive against the atmospheric pressure.
Extract ductwork shall be designed for ease of cleaning, with flanged joints and man-
size access doors, and shall be constructed of stainless steel sheet (type 304),
minimum thickness, 1.0 mm. Air velocities should be a minimum of 9 m/s. Extract
fans should be treated for moisture and heat, and attenuators should be avoided. A
point of grease and residue collection shall be provided at the base of each vertical
rise. An opening and drain trap shall be provided at each change in direction of the
duct for purposes of inspection and cleaning. This access door shall be made to be
removed without the use of tools.
The hood shall be equipped with stainless steel baffle type grease filter. The filter
housing shall terminate in a pitched, full length grease trough, which shall drain into a
stainless steel removable grease container. Any noise from the filter shall not be
acceptable. The drain line shall be provide and connected to drain point of hood.
Hood shall be provided with one (1) filter removal tool.
All external joints and seams are to be welded liquid-tight. The motor to an exhaust
fan is to be located outside the exhaust air stream. The ducts that terminate above
the roof has the discharge located a minimum 1000 mm above the roof surface and
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distance should be 20 meter between the exhaust point and any supply air intakes.
The discharge terminal device should include a bird guard mesh (made of SS grade
316) and protected from rain entertainment.
Comfort air conditioning should be provided by high level fan coil units.
The requirements for fire detection and protection in kitchens are included in SP-1075
Specification for Fire & Explosion Risk Management.

2.4.6 Laboratories
Laboratory air conditioning design shall be based on the specific requirements of the
laboratory work. The System shall provide adequate ventilation to remove fumes,
odours, airborne contaminants, and to safely operate fume hoods. They shall be
designed to maintain relative pressure differentials between spaces to prevent of
cross contamination. HVAC systems shall be reliable, redundant and operate without
interruption while being efficient to operate, both in terms of energy consumption and
from a maintenance perspective.
However, the following guidelines should apply.
HVAC system for Laboratory working and solvent storage areas should be provided
with 100% outside air system (with treatment), which also provide adequate
ventilation to offset fume hood exhaust and exhaust air requirements. Laboratory
supply air shall not be re-circulated or reused for other ventilation needs. In interior
Oman, heating should be included for winter morning start up. Ancillary areas, such
as offices, should be provided with separate, re-circulating systems such as fan coil
units. Mechanical exhaust should be provided for chemical and material storage
areas, typically at a rate of 6 – 15 air changes an hour, depending on the items
stored.
Fume cupboards for use with hydrocarbons should have an acid resistant 18/12
stainless steel internal fume chamber with integral bench top. The minimum air
velocity over a 400 mm deep sash opening should be 0.75 m/s.
Fume cupboards for general use should have 1 mm thick high-pressure plastic
laminate on the sides and solid epoxy resin bench tops. The minimum air velocity
over a 400 mm deep sash opening should be 0.5 m/s.
All fume cupboards should be provided with air foil sash opening profiles and high-
level by-pass grilles to ensure constant volume airstreams.
Fume cupboard exhaust ductwork shall be constructed of HDPE and shall not contain
fire dampers. Fire detection and alarm systems shall not be interlocked to
automatically shutdown laboratory hood exhaust fan.
Exhaust air from fume hoods shall be sterilized before being exhausted to the
outdoors and meet the requirements of ASHRAE HVAC Application Handbook.
The internal fume chamber, exhaust ducting and exhaust fan shall be classified as
Zone 1 hazard. The internal light fittings therefore shall be separated from the fume
chamber by an airtight glass plate. Solvent and gas bottle stores shall be classified
Zone 2.

2.4.7 Temporary Buildings

Air conditioning design parameters for temporary buildings, such as transportable
units, should be similar to those for permanent buildings. However, due to inferior
thermal conductivity characteristics, electric heating may be required.

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2.5 Appendices
Appendix 2.5A: Glossary of Definitions & Abbreviations
Appendix 2.5B: Internal Environment Design Criteria
Appendix 2.5C: Standard Forms

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Appendix 2.5A: Glossary of Definitions & Abbreviations

For the purposes of this document, the following definitions, terminology and abbreviations
shall apply.

2.5.A1 General Definitions & Terminology

Shall : The word 'shall' indicates a requirement

Should : The word 'should' indicates a recommendation

The Company : Petroleum Development Oman L.L.C.,

The Contractor : The party with which the Company has entered into a Contract

Manufacturer : A Party responsible for the manufacture of equipment and

services to perform the duties specified by the Consultant or
the Company.
Vendor/Supplier: : A party responsible for the supply of equipment, materials or
product related services in accordance with the purchase order
issued by PDO or its nominated purchasing office.
Local Agent : An authorised agent of a Manufacturer in the Sultanate Of
Oman who can supply the product and services.
National Product : A product defined as a National Product, in origin
manufactured in the Sultanate Of Oman as per the General
Conditions of Contract.
GCC Product : A product defined as a GCC Product, in origin manufactured in
GCC country as per the General Conditions of Contract.
Works : The permanent Works to be executed and maintained in
accordance with the contract together with all temporary works
of every kind required in or about the execution or maintenance
of the Works.
Workshop : A defined place, approved by the Company, where the
Contractor executes fabrication works.
Worksite : The land and other places on, under, in or through which the
Works are to be executed.
the User : The Company, and/or Consultant, designate using this
document.
Temporary : Any member or structure which needs to withstand loads and
Structures forces of a temporary nature, such as scaffolding, erection
bracing, steel props, commissioning facilities, etc. The word
‘temporary’ shall be understood as a short period, limited to
maximum of 2 years.
Semi Permanent : Any member or structure which needs to withstand all
Structures meteorological conditions, loads and forces of a permanent
nature, but designed for a short period. The word ‘semi-
permanent’ shall be understood as a relatively short period,
limited to maximum of 4 years.
Permanent : Any member or structure which needs to withstand all
Structures meteorological conditions, loads and forces of a permanent
nature, but designed for a long period. The word ‘permanent’
shall be understood as a relatively long period, say 30 years or
more.
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Size : When related to pipe work means nominal size, which

generally approximates to the bore of steel and plastic tubes,
the outside diameter of copper tubes etc.
Complete : “Complete installation” shall mean not only the major items of
installation plant and equipment conveyed by this specification, but all the
incidental sundry components necessary for the complete
execution of the works and for the proper operation of the
installation, with their labour charges, whether or not these
sundry components are mentioned in detail in the tender
documents issued in connection with the contract.

2.5.A2 Abbreviations
The following abbreviations are used in this document.
ASME : American Society of Mechanical Engineers

ASNT : American Society Non-Destructive Testing

ASTM : American Society for Testing and Materials

AWS : American Welding Society

BS : British Standard

CIBSE : Chartered Institute of Building Services Engineers

CFDH : Corporate Functional Discipline Head

CP : Code of Practice

DB : Dry Bulb Temperature

DEP : Design and Engineering Practice (SIEP / Shell GSI

Standard)
DIA : Diameter

DIN : Deutsche Institute for Normung (West German Institute for

Standardisation)
DRG : Drawing

EPC : Engineering, Procurement & Construction

ERD : Engineering Reference Document

ESD : Emergency Shutdown

EWC : European Water Closet

EXL : Existing Level

FFL : Finished Floor Level

FS : Full Size

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GCC : Gulf Cooperation Council

GI : Galvanised Iron

GRC : Glass Reinforced Concrete

GRE/GRP : (Fibre) Glass Reinforced Epoxy or Plastic

GRG : Glass Reinforced Gypsum

HDPE : High Density Polyethylene

HOR : Horizontal

HP : High Pressure

HSE : Health, Safety and Environment

HV : High Voltage

HW : Hardwood

IEE : Institution of Electrical Engineers

JE : Junior Employee

JS : Junior Staff

LPG : Liquid Petroleum Gas

LV : Low Voltage

MAF : Mina Al Fahal (PDO Coastal Centre of Operations)

MAX : Maximum

MBF : High Pressure Mercury Discharge

MIN : Minimum

MRME : Ministry of Regional Municipalities & Environment

N : Neutral

N/A : Not Applicable

No. : Number

NTS : Not to Scale

PDO : Petroleum Development Oman LLC

PPM : Parts per Million

SELV : Safe Extra Low Voltage

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Shell GSI : Shell Global Solutions International B.V.

SIC : Shell International Chemicals B.V.

SIEP : Shell International Exploration and Production B.V.

SP : Specification

SS : Senior Staff

SSL : Structural Slab Level

STD : Standard

UPS : Uninterrupted Power Supply

UPVC : Unplasticised Polyvinyl Chloride

UV : Ultra Violet

VERT : Vertical

WB : Wet Bulb Temperature

2.5.A3 Abbreviations for Building Types

The abbreviations used in this document for different building types are given in Table A.3.1
Table A.3.1: Building Type Codes
Code Building or Area
ABL : Ablutions
ABL/1 : Ablution Block – SS
ABL/2 : Ablution Block – JS
ABL/3 : Ablution Block – JE
ACC : Accommodation
ACC/1 : Accommodation – SS House
ACC/2 : Accommodation – SS Bachelor Flats
ACC/3 : Accommodation – SS Rooms
ACC/4 : Accommodation – JS Units
ACC/5 : Accommodation – JE Units
AIR : Air Terminal
AIR/1 : Air Terminal – Building
AIR/2 : Air Terminal – Sunshade

(Contd.)

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Table 2.5.A3.1: Building Type Codes (contd.)

ANC : Ancillary Building (Catering / Laundry)
ANC/1 : Ancillary Building – Main Camps
ANC/2 : Ancillary Building – Satellite Camps
CON : Control Building
CON/1 : Control Building – Type 1
CON/2 : Control Building – Type 2
CON/3 : Control Building – Type 3

ELE : Electrical Facility

ELE/1 : Electrical Installation – Substation
ELE/2 : Electrical Installation – Switch Yard
ELE/3 : Electrical Installation – Power Station

EXP : Explosives Store

FIR : Fire Station

FIR/1 : Fire Station – Type 1
FIR/2 : Fire Station – Type 2

GAR : Garage / Fuel Station

GAR/1 : Garage / Fuel Station – Type 1
GAR/2 : Garage / Fuel Station – Type 2
GAR/3 : Garage / Fuel Station – Type 3
GUA : Guard House
GUA/1 : Guard House
GUA/2 : Sentry Box

(Contd.)

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Table 2.5.A3.1: Building Type Codes (contd.)

Code Building or Area
HOS : Hospital / Clinic
HOS/1 : Clinic – Type 1
HOS/2 : Clinic – Type 2
HOS/3 : First Aid Post

KIT : Kitchen (Separate Building)

KIT/1 : Kitchen – SS
KIT/2 : Kitchen – JS
KIT/3 : Kitchen – JE

LAB : Laboratory
LAB/1 : Laboratory – Production Chemistry
LAB/2 : Laboratory – Geology

LAU : Laundry

MES : Mess / Canteen

MES/1 : Mess / Canteen – SS
MES/2 : Mess / Canteen – JS
MES/3 : Mess / Canteen – JE

MOS : Mosque
MOS/1 : Mosque – Permanent
MOS/2 : Mosque – Prayer Shelter

(Contd.)

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Table 2.5.A3.1: Building Type Codes (contd.)

Code Building or Area
OFF : Office
OFF/1 : Office – Solid Partitions
OFF/2 : Office – Demountable Partitions

REC : Recreational Facility

REC/1 : Recreational Facility – SS
REC/2 : Recreational Facility – JS
REC/3 : Recreational Facility – JE
REC/4 : Recreational Facility – Arts & Crafts
REC/5 : Recreational Facility – Cinema Indoor
REC/6 : Recreational Facility – Cinema Outdoor
REC/7 : Recreational Facility – Swimming Pool

ROS : Reverse Osmosis Plant (Utilities)

SCH : School/Training Centre

SCH/1 : Junior School
SCH/2 : Kindergarten
SCH/3 : Training Centre

SHO : Shop
SHO/1 : Shop – Bulk Store (Liquor)
SHO/2 : Shop – General Store

(Contd.)

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Table 2.5.A3.1: Building Type Codes (contd.)

Code Building or Area
SPO : Sports Facility
SPO/1 : Sports Facility – Squash Court
SPO/2 : Sports Facility – Sports Hall / Gym
SPO/3 : Sports Facility – Boat Centre
SPO/4 : Sports Facility – Golf Course
SPO/5 : Sports Facility – Tennis / Volleyball Court
SPO/6 : Sports Facility – Changing Rooms
SPO/7 : Sports Facility – Sports Field

STO : Store
STO/1 : Store – Edit and Seismic Tape
STO/2 : Store – File Archives
STO/3 : Store – Chemical
STO/4 : Store – Core Shed
STO/5 : Store – Loose Grain Store
STO/6 : Store – Cold Store
STO/7 : Store – Dry Store / Tinned Food Store
STO/8 : Store – Gas Bottle

STP : Sewage Treatment Plant

TEL : Telecommunications Facility
TEL/1 : Telecoms Buildings – Type A
TEL/2 : Telecoms Buildings – Type B
TEL/3 : Telecoms Buildings – Type C
TEL/4 : Telecoms Buildings – Type D

(Contd.)

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Table 2.5.A3.1: Building Type Codes (contd.)

Code Building or Area
TRU : Transportable Unit (Cabin)
TRU/1 : Temporary Accommodation
TRU/2 : Temporary Offices
TRU/3 : Temporary Store
TRU/4 : Temporary Mess
TRU/5 : Temporary Kitchen
TRU/6 : Temporary Ablution

WAH : Warehouse / Depot

WAH/01 : Warehouse / Depot – Non-Inflammable Material
WAH/02 : Warehouse / Depot – Personal Effects
WAH/03 : Warehouse / Depot – Furniture & Semi-Inflammable
WAH/04 : Warehouse / Depot – Inflammable Material

WOR : Workshop
WOR/01 : Workshop – Electrical & Air-conditioning
WOR/02 : Workshop – Mechanical
WOR/03 : Workshop – Instrument
WOR/04 : Workshop – Carpentry
WOR/05 : Workshop – Light Vehicle
WOR/06 : Workshop – Heavy Vehicle
WOR/07 : Workshop – Integrated

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2.5.A4 Abbreviations for Room Types

The abbreviations used in this document for different room types are given in Table 2.5.A4.1
Table 2.5.A4.1: Room Type Codes
Code Room Type
ALL : All rooms unless noted otherwise
BAKE : Bakery
BAR : Bar
BATH : Bathroom
BED : Bedroom
BLDG : Building
BTRY : Battery Room
CANT : Canteen
CDST : Cold Store
CHRM : Changing Room
CLNR : Cleaners Room
CLRM : Classroom
CONF : Conference Room
CORR : Corridor
CTRL : Control Room
DARK : Dark Room
DINE : Dining Room
DPFZ : Deep Freeze Store
DUCT : Service Duct
ELEC : Electrical Cupboard
ENTR : Entrance Hall
EQMT : Equipment Room
EXAM : Examination Room
FILE : Files Store

(Contd.)

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Table 2.5.A4.1: Room Type Codes (contd.)

Code Room Type

ICE : Ice Store

ISO : Isotope Pit

KTCH : Kitchen
LABC : Laboratory (Cores)
LABO : Laboratory (Oil)
LABW : Laboratory (Water)
LBRY : Library
LDRY : Laundry
LESR : Leisure
LIFT : Elevator
LNGE : Lounge/Sitting Room
MORT : Mortuary
OFF1 : 7 m2 Module Office
OFF2 : 10.5 m2 Module Office
OFF3 : Drawing Office
PARK : Parking Bay
PRAY : Prayer Room
PREP : Food Preparation
PROJ : Projection Room
PTRY : Pantry
REC1 : Recreation – Snooker Room
REC2 : Recreation – Table Tennis Room
RECP : Reception
REDX : First Aid Room
RSNT : Restaurant

(Contd.)

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Table 2.5.A4.1: Room Type Codes (contd.)

Code Room Type

SERV : Service Room

SH : Shower
SHOP : Shop
SL : Sluice
SQCT : Squash Court
ST/B : Gas Bottle Store
ST/C : Chemical Store
ST/D : Dry Store
ST/E : Equipment & Tools Store
ST/G : General Supply Store
ST/H : Health Dept Store (Poisons)
ST/K : Kitchen Consumables Store
ST/L : Bulk (Liquor) Store
ST/M : Medical (Drugs) Store
ST/O : Office Supplies Store
ST/S : Secure Store
ST/T : Edit & Seismic Tape Store
ST/U : UV Shielded Store
STND : Stand & Wait Area
STWL : Stairwell
SWGR : Switchgear Room
TLET : Public Toilet
TRMT : Treatment Room
TV : TV / Video Room
UTIL : Utility Room
VIEW : Viewing Gallery
WAIT : Waiting Room
WARD : Ward
WC : Toilet
WKSP : Workshop
XRAY : X-Ray Room

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Appendix 2.5.B: Internal Environment Design Criteria

Relative
Room Min Fresh Min Air Max Noise
Building Room Humidity
Temp 0C Air l/s Change Per h. Rate NR
%RH
Standard (Std.) 21 45-60 10/pers. 0.5 30
Project Specific * * * * *
Standard Rooms
BAR Std. Std. Std. 10 40
BATH ” ” No 6 40
BED ” ” Std. Std. 28
BTRY 22 Std. * 6 40
CANT Std. Std. Std. 8 40
CHRM ” ” ” 1 40
CLNR * * * * 45
CLRM Std. Std. Std. Std. 30
CONF ” ” Std. Std. 30
CORR Std. ” Std. Std. 40
CTRL Std. Std. Std. Std. 30
DARK ” ” No 6 35

ALL DINE ” ” Std. 8 40

ENTR ” ” * Std. 35
FILE ” ” ” ” 40
GYM ” ” Std. ” 40
ICE ” ” ” ” 45
LBRY ” ” Std. Std. 30
LNGE ” ” Std. Std. 35
OFF1 ” ” ” Std. 30
CTRL Std. Std. Std. Std. 30
DARK ” ” No 6 35
DINE ” ” Std. 8 40
ENTR ” ” * Std. 35
FILE ” ” ” ” 40

(Contd.)

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Appendix 2.5.B: Internal Environment Design Criteria (contd.)

Min Air
Room Relative Min Fresh Air Max Noise
Building Room Change Per
Temp 0C Humidity %RH l/s Rate NR
h
Standard (Std.) 21 45-60 10/pers 0.5 30
Project Specific * * * * *

Standard Rooms
OFF2 Std. Std. Std. Std. 30
OFF3 ” ” ” Std. 30
PRAY ” ” ” Std. 30
PROJ ” ” Std. Std. 30
RECP ” ” Std. Std. 35
RSNT ” ” Std. 8 40
SHOP ” ” Std. Std. 40
SQCT ” ” Std. ” 40

ALL SERV ” ” Std. ” 45

SH No No No 6 45
ST/O ” ” ” Std 45
SWGR Std. Std. * Std. 40
TLET Std. No Ni 6 45
TV Std. Std. Std. Std. 35
UTIL ” ” * 1 45
VIEW ” ” ” Std. 40
WAIT ” ” ” Std. 40
DPFZ Std. Std. No Std. 45
ANC (ALL) LDRY 24 max No * Std. 45
ST/K Std. Std. * Std. 40
CON (ALL) AUX Std. Std. * Std. 45
EXAM Std. “ Std. Std. 35

HOSP MORT ” ” * ” 35
(ALL) RECP ” ” Std. ” 35
REDX ” ” Std. ” 35

(Contd.)

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Appendix 2.5.B: Internal Environment Design Criteria (contd.)

Min Air
Room Relative Min Fresh Air Max Noise
Building Room Change Per
Temp 0C Humidity %RH l/s Rate NR
h
Standard (Std.) 21 45-60 10/pers. 0.5 30
Project Specific * * * * *

Standard Rooms

ST/M Std. Std. * Std. 40

TRMT ” ” Std. ” 35
HOSP (ALL)
WARD ” ” ” ” 35
XRAY ” ” ” ” 35
PTRY Std. Std. * 6 Std
KIT(ALL) PREP ” ” * 6 40
ST/K 24 max ” No Std. 45
CORR Std. Std. * * 40
LABO ” ” * 6 minimum 40
LAB (ALL)
LABW ” ” * 6 minimum 40
ST/B * No * 1 45
ST/F C Std. Std. * * 40
REC1 Std. Std. Std. Std. 40
REC2 ” ” Std. Std. 40
MES (ALL)
ST/E No No No ” 40
ST/L Std. Std. ” ” 40
SCHO (ALL) KTCH Std. Std. No * 40
ST/B * * * * 45
STO (ALL)
ST/C * Std. No * 40
” ” ” 40
WAH (ALL) ST/H *

(Contd.)

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Appendix 2.5.B: Internal Environment Design Criteria (contd.)

Min Air
Room Relative Min Fresh Air Max Noise
Building Room Change Per
Temp 0C Humidity %RH l/s Rate NR
h
Standard (Std.) 21 45-60 10/pers. 0.5 30
Project Specific * * * * *
Standard Rooms
ST/M Std. Std. No 6 40
WAH (ALL) ST/T 22 502 ” Std. 40
ST/U * * * * 40
WOR/1 WKSP * * * * *
WOR/2 WKSP * * * * *
WOR/3 WKSP * * * * *
WOR/4 WKSP * * * 6 *
WOR/5 & /6 WKSP * * * 6 *

Note: * = Project Specific Requirements

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Appendix 2.5.C: Standard Forms:

Ref No Description
C.1 STD-2-1702-A01 : Pipe work Leakage Test
C.2 STD-2-1702-A02 : Exceptions List
C.3 STD-2-1702-A03 : Handover Report

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2.5.C1 Test Report for Pipe Work Leakage (STD-2-1702-A01)

Contract: Contractor: System:
Service
Service Medium Working Pressure kPa
Test Medium Test Pressure kPa
TEST
Section Location Duration Comments

Notes: Pipe work leakage tests shall be conducted in accordance with Specification

WITNESSED
Sheet No: for Contractor: for PDO:
Date: Position: Ref Ind:

O Original Issue Petroleum Development Oman

Rev Date Description Approved

BUILDING SERVICES TEST REPORT DRW AREA ENG SERIAL SHEET PROJ DWG REV
NO CODE SECT NO CODE SIZE

Title PIPEWORK LEAKAGE STD 2 1702 A01 A4 O

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2.5.C2 Exceptions List (STD-2-1702-A02)

Contract: Contractor: System:

Item No Description Raised Cleared Comments

Date By Date By

NOTES:
DISTRIBUTION
Update
Sheet No.

O Original Issue Petroleum Development Oman

Rev Date Description Approved
CIVIL & BUILDING FACILITY DRW AREA ENG SERIAL SHEET PROJ DWG REV
CODE SECT NO CODE SIZE

Title EXCEPTIONS LIST NO STD 2 1702 A02 A4 O

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2.5.C3 Handover Report (STD-2-1702-A03)

Contract No: Title: Facility:
CONSTRUCTION COMPLETION
CIVIL WORKS Ref Ind
Comment: TA
Signature
Date
AIRCONDITIONING INSTALLATION Ref Ind
Comment: TA
Signature
Date
PLUMBING INSTALLATION Ref Ind
Comment: TA
Signature
Date
FIRE PROTECTION INSTALLATION Ref Ind
Comment: TA
Signature
Date
ELECTRICAL INSTALLATION Ref Ind
Comment: TA
Signature
Date
TELECOMS INSTALLATION Ref Ind
Comment: TA
Signature
Date

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2.5.C3 Handover Report (STD-2-1702-A03)

DATACOMS INSTALLATION Ref Ind
Comment: TA
Signature
Date
FACILITY HANDOVER
CONSTRUCTION SUPERVISOR PROJECT ENGINEER ASSET CUSTODIAN
Ref Ind Ref Ind Ref Ind
Signature Signature Signature
Date Date Date
Comment: Comment: Comment:

O Original issue Petroleum Development Oman

Rev Date Description Approved
CIVIL & BUILDING FACILITY DRW AREA ENG SERIAL SHEET PROJ DWG REV
CODE SECT NO CODE SIZE

Title HANDOVER REPORT NO STD 2 1702 A03 A4 O

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Section 3: Heating, Ventilation & Air-Conditioning

Materials & Works

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3.1 Introduction

This specification covers the technical requirements for the furnishing &installation of equipment,
final testing, adjusting, and balancing of all heating, ventilating and air-conditioning system.
3.2 Scope

3.2.1 General
This Specification shall define the physical characteristics of the suitable materials
and describes the Works based on product or a method of Specifications. This
Specification shall also define the type of testing requirements and test sheets to be
used.
Plant and non-plant buildings require climatic conditioning (i.e. air conditioning and
ventilation) in order to maintain the temperature, relative humidity and air quality
within defined limits. In this way reliable operation of electronic equipment and
human working conditions are enhanced.
HVAC systems are generally supplied by specialised Manufacturers as package
units or as single components. Standard industrial HVAC equipment should be used.
It shall be ensured that sufficient space in buildings is reserved for HVAC equipment
and its ducting.
3.2.2 Abbreviations
General abbreviations are given in Section-2 Specification for HVAC Services –
‘General Requirements’. The following additional abbreviations have been used in
this document.
DB - Dry Bulb Temperature
HDPE - High Density Polyethylene
HRC - High Rupturing Capacity
WB - Wet Bulb Temperature
AHU - Air Handling Unit
3.2.3 Definitions
For the purpose of this Specification, the following definitions shall hold:
3.2.3.1 General Definitions

The Contractor is the party which carries out all or part of the design, engineering,
procurement, construction, commissioning or management of a project or operation
of a facility. The Principal may undertake all or part of the duties of the Contractor.
The Manufacturer/Supplier is the party which manufactures or supplies equipment
and services to perform the duties specified by the Contractor.
The Company is the party which initiates the project and ultimately pays for its
design and construction. The Company will generally specify the technical
requirements. The Company may also include an agent or consultant authorised to
act for, and on behalf of, the Company.
The word shall indicate a requirement. The word should indicate a
recommendation.

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3.2.3.2 Specific Definitions

Air Handling Unit (Re-circulation): HVAC equipment through which air is

transported and transformed to the required conditions by filtration, heating and
cooling (including humidification/dehumidification by means of condensation). Re-
circulation air handling units may form part of an HVAC ducting system.
Air Handling Unit (Self-contained): An air handling unit, located in the space which
it serves, which re-circulates the air in that space to the required conditions. A self-
contained air handling unit does not normally involve a ducting system.
Chilled Water Unit (Air cool type): A unit similar to a direct expansion (DX) chiller
but including a heat exchanger which utilises the vaporising refrigerant's latent heat
to cool a chilled water circuit to the required temperature.
Direct Expansion (DX) Chiller: A unit consisting of a compressor and a condenser.
The refrigerant vapour is compressed to a certain pressure, condensed to liquid
refrigerant and then vaporised, thus utilising the vaporising refrigerant's latent heat in
a cooling coil (separate from the chiller). The vaporised refrigerant is returned from
the coil to the compressor.
(Dry-bulb) Temperature: The temperature of the air indicated by an accurate
thermometer.
Electronic/Electrical Equipment: Indoor electronic and electrical equipment,
including microprocessor based control, safeguarding, telecommunication, computer,
power supply and switchgear systems.
Fan Coil Unit: HVAC equipment through which air is re-circulated from the space in
which it is located. The purpose of this re-circulation is to cool or heat this air to the
conditions required for the space. This unit is normally connected to the chilled water
system.
Fresh air Ventilation Unit: An air handling unit in which the fresh air is handled to
the required conditions and used as ventilation air.
Human Comfort: Is defined by the environmental parameters of temperature,
radiation, humidity and air movement necessary for thermal comfort and depends on
the individual’s clothing and activity level. In a control building occupants will typically
be sedentary or slightly active and wearing indoor clothing.
Humidity (Relative): The ratio of the weight fraction of water vapour present in the
air to the weight fraction of water vapour present in saturated air at the same
temperature and barometric pressure.
HVAC System: A heating, ventilation and air-conditioning system which maintains
the temperature, relative humidity and air quality in a room or building within defined
limits.
Interruptible, Maintained Electrical Supply: A source of electrical power which is
backed up by a second (emergency) source of power to provide a supply of
electricity that may be interrupted for no more than 15 s.
Buildings: Buildings such as offices, all non-plant buildings, control buildings, field
auxiliary rooms (FARs), analyser houses, electrical substations and others (e.g.
dedicated flow metering buildings). Such buildings may contain different types of
rooms. HVAC electrical equipment shall be suitable for the applicable hazardous
area. Refer to DEP 32.31.50.13-Gen. for further safety requirements for analyser
houses.
Uninterruptible Maintained Electrical Supply. A source of electrical power, which
is backed up by a second (emergency) source of power to provide a supply of
electricity that may be interrupted for no more than 0.5 minutes.

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Vital electronic equipment: Electronic equipment which, if failing in operation or

when actuated, can cause a process upset, an unsafe condition of the process
and/or electrical installation, can jeopardise life, or can cause major damage to the
installation.
Vital HVAC system: A HVAC system meant for vital rooms only.
Vital rooms: Rooms containing vital electronic equipment (e.g. computer rooms,
instrument auxiliary room, electrical auxiliary room, telecommunications room) and
continuously manned rooms (e.g. control room).
3.2.4 Automation Controls

HVAC control and alarm systems shall be in line with the HVAC vendor's standards.
HVAC control systems should at least include the following:
(a) Temperature control
- For constantly manned rooms (e.g. control room, shift supervisor room);
- For certain rooms which are less frequently used (e.g. meeting rooms, mess
rooms etc.);
- For equipment rooms and buildings (e.g. instrument auxiliary room, electrical
auxiliary room, computer room, electrical substations and FARs).
(b) Humidity control
- For all rooms and buildings;
Control systems shall normally operate in automatic mode but manual operation
shall be possible.
HVAC alarms shall be individually displayed on local HVAC panels. Common HVAC
alarm signals generated by the HVAC control system and displayed on the DCS
screen in the main control room shall be routed either via potential-free contacts and
interface boxes or via software links.
Control signals coming from an HVAC control system cabinet and going to an HVAC
motor control centre (power) panel shall pass via an interface box. The HVAC control
panel and the motor control centre (power) panel shall be physically separated. For
central air handling units, both panels should be located as per project requirements
subject to company approval.
The HVAC control panel shall be protected with 4 levels of password.
The requirements for the automatic control of air conditioning systems are given in
‘Electrical Works’ Chapter.
3.2.5 Units of Measurement

Units of measurement are listed in ‘General Requirements’ Section-2 and item 2.2.2
page 16.

3.3 Chilled Water System

3.3.1 Air Cooled Water Chiller

3.3.1.1 General
Provide factory assembled and tested air-cooled liquid chiller, suitable for outdoor
installation, to operate at a wide range of ambient temperature from “-4ºC” to “60ºC”.
Chiller shall include but not be limited as compressors, evaporator, condensers,
electronic expansion valves, inter connecting piping & wiring and control panels.
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Engrave plate and labelling shall be provided for each chiller components .Engrave
plate shall be of stainless steel.
The chiller shall be designed to cooling chilled water temperature as 4ºC to 12ºC.
Chiller capacity selection shall be based on a water side fouling factor 0.018 m²
ºC/kw in the evaporator tubes and the dry bulb temperature entering the air cooled
condenser. The unit shall be able to start with an evaporator entering high fluid
temperature.
The chiller unit shall consist of two compressors minimum and minimum two
independent refrigerant circuits shall be provided. Compressor shall be mounted on
a single welded steel base.

Chiller shall be performance tests/run tested at the manufacturer’s works under

simulated design conditions. Such tests shall be witnessed and approved by the
Company’s engineer(s). Prior to shipment, the chiller automated controls test shall
be executed to check for proper wiring and ensure correct controls operation, the
unit shall be pressure tested, evacuated and fully charged with refrigerant.

3.3.1.2 Fluids
Provide full operating charge of refrigerant, oil and all other fluids as required for
proper operation. Refrigerant shall not contain chlorine. The unit shall be charged
with environment friendly, ozone friendly and low global warming potential
refrigerant. Contractor shall evaluate the available environmentally friendly
refrigerant and submit to Company for approval during the design review and before
ordering the chiller.

3.3.1.3 Housing
Provide manufacturer’s equipment housing, constructed for outdoor installation with
corrosion protection coating and exterior finish. The casing of unit shall be made of
zinc coated galvanized steel sheets which is phosphatised and backed after an
electrostatic powder coat of 60 microns. This finish and coating can pass a 1000
hour in 5% salt spray testing at 35 ºC and 95% RH. The test certificate has to
submit to company.
The unit structure shall be made of heavy gauche, galvanized steel coated with
backed- on enamel. Base rail hall be of formed double thickness, painted galvanized
plate steel or stainless steel.
Provide removable panels and/or access doors of same material and same finishing
used for casing, for inspection and access to internal parts and components. Door
shall be provided with special gasket and locking device.

3.3.1.4 Evaporator
Provide shell and tube design with seamless copper tubes with minimum wall
thickness 0.71mm, roller expanded into tube sheets. Design, test, and stamp for
refrigerant side working pressure of 1550 kPa minimum and water side working
pressure of 1034 kPa minimum in accordance with ASME pressure vessel code or
equivalent European codes. Provide one water pass with series of internal baffles.
Provide 1034 kPa flanged water connections. Provide water drain connection with
stainless steel valve and bulb wells of copper /brass for temperature controller and
low temperature cut-out at 3- 4ºC.
Provide independent multiple refrigerant circuit’s gasket evaporator heads. The
evaporator shell shall be insulated with 25mm closed –cell with a maximum K factor
of 0.038w/m.ºK. Evaporator thermal insulation shall be flexible elastomeric
complying ASTM C 534, type II, apply adhesive to 100 percent of insulation contact

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surface to give good rigidity, after adhesive apply two coats of protective coating to
insulation, factory apply insulation over entire surfaces of water chillers component,
factory fitted with aluminium cladding thickness 0.3mm minimum to provide
mechanical protection and ensure protection against UV rays.
Chiller shall have only one water inlet & outlet connection. The evaporator shall be
tested with nitrogen pressurised dry, water and oil pressure are not acceptable.
Refrigerant side test pressure of 2325 kPa (24 bar) and water side test pressure of
1551 kPa(16 bar) minimum. In top of the insulation metal cladding of 0.55mm
thickness shall be provided to the evaporator and the suction line.

3.3.1.5 Condenser
Construct coils with copper headers and configured aluminium or copper/copper fins
& tube mechanically bonded to seamless copper tubing. Provide integral sub-cooling
circuit with liquid accumulators.
Condensers coils shall be coated with here-site or approved equivalent to prevent
corrosion. Coating shall be guaranteed for 10 years. The Fins spacing shall be
depends on number of coil row of condenser coil. The condenser coils shall be leak-
tested by nitrogen/helium gas detection at 450 psig (3150 kpa). Provide removable
guard factory mounted with wire mesh heavy gauge, electro-galvanized or
polyethylene coated to full unit.
Condenser fans: Condenser fans shall have high ambient fan motors with corrosion-
resistant blades such as heavy gauge aluminium. Provide propeller fans, direct
driven, draw-through vertical discharge design, statically and dynamically balanced.
Provide permanently lubricated ball bearing motors with 3-phase overload
protection, thermal protection. Provide protective grill over air discharge. Fan
assemblies shall be provided with heavy gauge, close mesh, electro-galvanized or
polyethylene coated fan guards.
Condenser fan shall be low noise, directly driven, with rpm not to exceed 950. The
fan impeller shall be multi blade type.
Fan motors shall be rated for outdoor use IP 65 protection with minimum efficiency
of 80%.Fan motors shall be drip-proof, with built-in individual over load protection via
a circuit breaker, class F Motor winding and starting contactors. Motors shall be
mounted on vibration isolators. Provide operation sequence of fan. Motor shall be
driven by 415 volts, 3 phase/ 240 volts single phase, 50 Hertz in accordance with
electrical specification Sp-1109 and relevant standards.

3.3.1.6 Compressor
Screw Compressor: The semi-hermetic screw compressors shall be the twin rotor-
type with direct drive, with internal relief valve and check valve, refrigerant gas-
cooled motors. Each compressor shall have a lubrication system including an oil
filter, a crankcase heater, suction and discharge shutoff valve, an oil level sensor, oil
sight glass, oil charging valve, and an oil pressure sensor.
Capacity control shall be provided by pilot operated solenoid valve capable of
reducing unit capacity to 15% of full load. Motor shall be cooled by suction gas and
protected by internal winding temperature sensors. Lube oil system shall include
external filter capable of filtration to 3 microns.
Each compressor shall be mounted on neoprene vibration isolators within the chiller
housing. Vibration isolators shall have an isolation efficiency of no less than 95 per
cent. Each compressor and oil separator shall be installed within an insulated
acoustic enclosure to reduce noise break out with removable panels to facilitate
services access. Compressors should conform to relevant API standards and
Design general specification.

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Centrifugal Compressor: The compressor shall be single stage centrifugal type

powered by an open drive electrical motor. The housing shall be fully accessible with
vertical circular joints, with the complete operating assembly removable from the
compressor and scroll housing. Compressor casting shall be designed for the
highest working pressure and hydrostatically tested in accordance with the design
standard. The rotor assembly shall consist of a heat-treated alloy steel driveshaft
and impeller shaft with cast aluminium, fully shrouded impeller. The impeller shall be
designed for balance thrust, dynamically balanced and over speed tested for
smooth, vibration-free operation. Insert –type journal and thrust bearing shall be
fabricated of aluminium alloy, precision bored and axially grooved.
Internal single helical gears with crowned teeth shall be designed so that more than
one tooth is in contact all the times to provide even distribution of compressor load
and quiet operation. Each gear shall be individually mounted in its own journal and
thrust bearings to isolate it from impeller and motor forces. The shaft seal shall be
spring loaded carbon ring with precision lapped collar cooled by oil during operation.
A gravity- fed oil reservoir shall be build into the top of the compressor to provide
lubrication during coast down in the event of a power failure.
Compressor Motor: The compressor motor shall be an open squirrel cage induction
motor. The open motor shall be provided with a D-flange, bolted to the cast iron
adapter mounted on the compressor to allow the motor to be rigidly coupled to the
compressor to provide factory alignment of motor and compressor shafts. Motor
drive shaft shall be directly connected to the compressor shaft with a flexible disk
coupling. The coupling shall be off all metal construction with no wearing parts and
no lubrication requirements.
Reciprocating Compressor: The compressor shall be accessible, semi-hermetic,
reciprocating compressors. All rotating parts shall be statically and dynamically
balanced.
The compressor motors shall preferably be of an open squirrel cage type with
overload protection in each phase. The terminal boxes shall be IP 65. Starting can
be done by part winding or start/delta connectors.
The compressor housing shall be cast iron, and contains removable cylinder heads
with internal muffling, suction and discharge service valves, crankcase sight glass
and heater, oil and suction strainers, and internal relief valves.
The crankshaft shall be ductile (nodular) iron, drilled for positive oil distribution, with
integral counterweights for balancing. The main bearing shall be insert type, steel
backed Babbitt. The thrust bearing shall be bronze.
Cylinder assemblies: suction and discharge valves are high-quality, non flexing,
stainless steel. The pistons shall be aluminium alloy with two piston rings. The
connection rods shall be aluminium alloy with integral bearings surfaces on both
ends. Cylinder liners shall be removable.
Semi-hermetic compressors shall include the following features:
 All parts of the electric motor shall be proof against contact with refrigerant and
the lubricating oils associated systems.
 The oil lubrication system
 Where motor rotor is overhang, a support bearing of adequate width shall be
provided.
 Additional thermal motor protection shall be provided against failure or partial
failure of the gas cooling system.

3.3.1.7 Capacity Modulation (Screw Compressor)

For screw chillers, provide capacity control by means of a hydraulically activated
slide valve located below the rotating screw rotors. Capacity control shall be based

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on leaving water temperature. The leaving water temperature sensor shall be factory
furnished and installed. Provide step-control by means of un-loader system, based
on ambient temperature/leaving water temperature. The leaving water temperature
sensor shall be factory furnished and installed. Hot gas bypass shall be provided
with chillers to allow a more stable leaving water temperature control at light load
condition.

Capacity Modulation (Centrifugal compressor):

Capacity control shall be achieved by use of pre-rotation vanes to provide fully
modulating control from full load to minimum load. Pre-rotation vane position shall be
automatically controlled by an external electric actuator to maintain constant leaving
chilled water temperature.

Capacity Modulation (Reciprocating compressor):

Capacity control shall be provided by solenoid actuated, capacity control valves,
which are controlled by the microprocessor centre. Gas flow shall be sufficient at all
times to cool the motor. The chiller shall be of multi compressors with independent
refrigerant circuits.

3.3.1.8 Refrigerant Circuit

Provide the following for each refrigerant circuit:

Liquid line solenoid valve

Replaceable- core type Filter dryer. Individual core holders treated against corrosion
by zinc-coating, with a reduced course for easy core replacement.

Liquid line sight glass with moisture indicator, material Brass/stainless

steel/aluminium.

Electronic expansion valve with the functions of automatically adjusting refrigerant

flow rate to make the air conditioner be in the best operation state and realizing good
energy conversation and high precision in temperature control.

Insulated suction line with 19 mm thickness closed cell elasometer with smooth
vapour barrier insulation and with aluminium cladding thickness 0.3mm.

Suction and discharge manual shutoff valves, material brass.

High side pressure relief device. Assembly shall conform to ASME Boiler and
Pressure Vessel Code. Assembly shall be sized and rated for chiller capacity.
Assembly shall function according to ASHRAE 15-1992, Safety Code for Mechanical
Refrigeration, Section 10.4.5.
Pressure switch shall have alarm contacts suitable for use with a remote audible,
visual alarm, or the building management/ DDC system.

3.3.1.9 Electrical Requirements

Power/control Panel: IP65 powder painted steel cabinets with hinged latched, and
gasket sealed outer doors equipped with wind struts for safer servicing. Provide
main power connection, compressor starters and fan motor contactors, current
overloads, and factory wiring. Panel shall include control display access door.
All starters, contractors, relays, heaters, etc. required for proper chiller operation
shall be provided by the chiller manufacturer, and shall be located within the
equipment provided.

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The chiller unit shall have a single point connection for field power wiring, 3 phase of
schedule voltage, 50 Hz. Circuit breaker shall be provided at point of incoming single
point connection to provide means of disconnecting and short circuit protection. Circuit
breaker shall be equipped with lockable operating handle that shall extend through
power panel door so that power may be disconnected without opening any panel
doors.
Provide a factory mounted, non-fused disconnect switch. The chiller unit shall have a
single point connection for control power wiring. The control circuit voltage shall be
24V/240 V, supplied by a factory-installed transformer. All electrical equipment shall be
in accordance with electrical specification Sp-1119 and relevant standards.
Starting current shall not exceed compressor full load amps. Exposed compressor and
fan motor power wiring shall be routed through conduit.

Provide equipment with power factor correction capacitors as required to maintain a

power factor of 95% at all load conditions.

3.3.1.10 Chiller Control

The chiller shall be furnished complete with a microprocessor/microcomputer based
control package fully installed, calibrated and ready for operation. Control components
as a minimum shall include a microprocessor/microcomputer, power and control circuit
terminal blocks, on/off switch, replaceable solid-state relay panel, thermistors, anti-
recycle timers, condenser fans, evaporator heater, unit alarm contacts, run signal
contacts, and potentiometers.

The diagnostics display module shall indicate the safety lockout condition by a numeric
or other suitable coding at the control panel, and shall be able to scroll an explanation
for the coded condition. The diagnostic display module shall have the capability of
displaying the output (result) of run tests to verify operation of each chiller component
(fan, compressor, switch, etc.) before chiller is started.
Capacity control based on leaving chilled water temperature 5ºC with return chilled
water sensing.
Unit controls shall include a microprocessor board and 80 characteristic digit
diagnostic display as a minimum that is capable of achieving the following function.
 Automatic changeover between compressors.
 Limiting the chilled water temperature pull down rate at start up to an adjustable range
0.1 to 1.1ºC per minute to prevent excessive demand spikes at start up.
 Enable chilled water leaving temperature adjustment based on return water
temperature.
 Provide a dual set point for the leaving chilled water temperature activated by a remote
contact closure signal
 Control water pump operation
 Enable automatic lead lag of two chillers in a single system
 The interlock system shall be provided between the chillers and AHU’s.
 No interlocking between compressors within one chiller.

3.3.1.11 Chiller Control Functions

The chiller control system shall have the capability to perform the following functions.
Manual or automatic star-up and shutdown time schedule.
Automatic lead-lag switching of compressor.
Compressor anti –cycling protection.
Each compressor running hours.

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Pump-out at the beginning and end of every circuit cycle.

Capacity control based on leaving chilled water temperature or entering water
temperature, and compensated by rate of change of return water temperature.
Limit the chilled water temperature pull down rate at start-up to 0.5ºC per minute to
prevent excessive demand spikes at start-up.
Provide a time delay of chiller stop/start. This time delay shall be selected according
user requirement and volume of the chilled water circuit (e.g.8 minute).

3.3.1.12 Chiller Protection

The chillers shall be provided by the thermistors, potentiometers and all necessary
components operating in conjunction with the control system to provide the following
safety functions.
Loss of refrigerant charge protection
Low chilled water flow protection.
Low chilled water temperature/Anti-freeze protection (manual reset).
Low and high superheat protection.
Low oil protection for each compressor circuit
Low & high control voltage to ±10% of 415 volt unit protection.
Low current protection for each circuit
Compressor thermal overload protection (manual rest)
Compressor pressure overloads protection (manual rest)
Compressor electrical overload protection (manual rest). Electrical overload through
the use of definite-purpose contactors and calibrated, ambient compensated,
magnetic trip circuit breakers. Circuit breakers shall open all 3 phases in the event of
an overload in any one phase (single-phasing condition).
Fan motor over-current protection
Phase protection.

3.3.1.13 Remote Chiller Control Interface

The chiller control system shall be suitable for the following remote control system
interface but not the limited from HVAC panel, DCS and Scada system:

- Remote auto (start)/stop capability.

- Remote run indication capability.

- Remote individual alarm capability.

- Remote chilled water flow switch interlock capability.

3.3.1.14 Flow Switch

The vendor shall furnish a flow switch for field installation the flow switch shall be
suitable for mounting in horizontal pipe. The flow switch shall be Pitot tube flow Multi-
port averaging type flow sensor designed to sense the velocity of a fluid flowing in a
pipe and produce a pressure output that is proportional to the fluid velocity.

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3.3.1.15 Motors
Motors for all HVAC equipment shall be in accordance with electrical specification
Sp-1119 and relevant standards.

3.3.1.16 Building Control System Interface

The chiller control system shall have the ability to interface and communicate directly
to the building control system without the use of additional field installed hardware
and software. If building control system and the chiller supplier are different the
chiller shall be supplied with a data port module which shall translate the information
in the chiller microprocessor to an ASCII stream of data which can be read by any
manufacturer’s building management control system.

3.3.2 Pipe Work

Pipes and fittings shall be in conformance with the following unless specified
otherwise:

3.3.2.1 Chilled Water Pipe

a) Design working pressure to be 16 bars for all pipe work, fittings, valves and
equipment unless stated otherwise. Contractor to ensure that all components of pipe
work installation are suitable for the working pressure and test pressure to be
supplied.

b) Pipes for chilled water installed above grade shall be seamless black Mild
steel, heavy weight to BS EN10255 or equivalent with ASTM A53 Schedule 40.

c) Pipes shall be painted with two coats of red oxide primer prior to application
of thermal insulation.

d) Fittings for chilled water:

65 mm and larger
i) Wrought carbon steel to ANSI B 16.9, butt-weld fittings.

50 mm and smaller
ii) Malleable iron to ASME B 16.3 with threads ends.

iii) Flare connections may be used on soft copper tubing where one end of the
flare connection is an integral part of the equipment or valve.

iv) Welding flanges for pipe 65 mm and larger: Steel to ASME B 16.5.

v) Unions for pipe 50 mm and smaller shall be Malleable iron ASTM A197, class
150, with bronze to iron ground joint, ANSI B 16.3

vi) Dielectric unions shall be used in case of joining dissimilar material.

vii) Flange Accessories: Gasket, canvas reinforced neoprene to BS 1737. Bolts,

square head machine with hexagonal nut, galvanized steel to BS 916.

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3.3.2.2 Refrigerant Pipe

Field refrigerant piping for direct expansion HVAC systems shall be seamless,
refrigerant quality copper confirming with ASTM B280 and ANSI B31.5, supplied with
sealed ends. Joints shall be avoided and shall be subject to Company approval.
Valve strainers, dryers, moisture indicators, sight glasses, and vibration eliminators
shall be full line size.

3.3.2.3 Condensate Drain Pipe

Pipe work shall be UPVC to BS EN 1452, Class E, with solvent cement joints and
injection moulded rigid PVC fittings, with a union at the tray connection and trap prior
to the drainage connection.

3.3.3 Valves (Chilled Water)

3.3.3.1 Isolating Valves

Isolating valves, size 65 mm and over, shall be to BS EN 1171, cast iron gate valves
with solid wedge, inside screw, non-rising stem and flanges to PN 16, approved by
the Company.

Isolating valves, size 50 mm and under, shall be to BS EN 12288, bronze gate

valves with solid wedge, non-rising stem and screwed BSPT ends, approved by the
Company.

3.3.3.2 Double Regulating Valves

Regulating valves, size 65 mm and over, shall be to BS EN 1171, cast iron double
regulating valves with metal to metal seat, outside screw, rising stem and flanges to
PN 16, approved by the Company.
Regulating valves, size 50 mm and under, shall be to BS EN 12288, bronze orifice
valves with non rising stem, screw bonnet and screwed BSPT ends, approved by the
Company.

3.3.3.3 Chilled Water Commissioning Valve Sets

All valves shall be approved by the Company.

Valve sets, sizes 15 mm to 50 mm, shall comprise bronze metering station, close
coupled, bronze double regulating valve located on the return, together with an
isolating valve on the flow.

Valve sets size 65 mm and above, shall comprise PN 16, cast iron metering station,
close-coupled, cast iron double regulating valve located in the return, together with
an isolating valve on the flow.

The test set shall comprise a single column type manometer connected to measure
the pressure difference across the metering station. The test set shall be supplied
with bypass and isolating valves and lengths of connecting tubing, terminating in
probe units.

3.3.3.4 Non-Return Valves

Non-return valves, size 65 mm and over, shall be to BS EN 12334, PN 16, cast iron
swing check valves with flanged bonnet, cast iron disc, bronze disc face and flanges
to PN 16, as approved by the Company.

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Non-return valves, size 50 mm and under, shall be to BS EN 12288, PN 25, bronze

swing check valves, with screwed bonnet, metal to metal seat and screwed BSPT
ends, as approved by the Company.

3.3.3.5 Strainers
Strainers, size 65 mm and over, shall be Y pattern with cast iron body, 1.5 mm
stainless steel screen and flanges to PN 16, as approved by the Company.
Strainers, size 50 mm to 32 mm, shall be Y pattern with bronze body, 1 mm brass/
stainless steel screen and screwed BSPT ends, as approved by the Company.
Strainers, size 25 mm and under, shall be Y pattern with pressed brass body, 1 mm
brass/stainless steel screen and screwed BSPT ends, as approved by the Company.

3.3.3.6 Terminal Units

Valves for chilled water fan coil unit’s connections, etc, shall be to BS 2767, bronze
union valves, angle or straight pattern, with proportional flow characteristics, plastic
cover hand wheel, as approved by the Company.
Return valves shall be lock shield. Where visible, valve bodies should have a
polished finish.

3.3.3.7 Safety Valves

Safety valves, size 50 mm and under, shall be to BS 759, bronze body with flat
seating surfaces and precision lapped to give positive closure.

3.3.3.8 Air Cocks

Air cocks on low pressure systems shall be size 6 mm, with loose keys, as approved
by the Company.

3.3.3.9 Automatic Air Vents

Automatic air vents shall be 15 mm, float type, air eliminators, as approved by the
Company.

3.3.3.10 Drain Cocks

Drain cocks, size 32 mm and over, shall be bronze gland cocks, complete with
malleable iron levers and hose unions, as approved by the Company.
Drain cocks, size 25 mm and under, shall be to BS 2879, Type A, bronze draining
taps, screw down pattern, lock shield with loose key, as approved by the Company.

3.3.3.11 Valves (Refrigerant)

a) Design, Manufacture, and test valves specifically for the service intended.
Comply with applicable ARI requirements. Provide removable internal parts for
inspection and replacement without applying heat and breaking pipe
connections. Direction of flow shall be legibly and permanently indicated on the
valve body.

b) Globe and angle refrigerant valves shall have either forged brass or bronze alloy
bodies, be back-seating type, and shall have packed stem and seal cap. Valves
65 mm (7/8 inch) outside diameter and smaller shall be pack less type having
hand wheels and bodies with brazing ends. Bonnets shall be replaceable while

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the valve is in place. Valves shall be rated for 450 psig maximum working
pressure and 135 °C (275 degree F) maximum operating temperature.

c) Check valve small than 65 mm (7/8 inch): 500 psig maximum operating
temperature, 150°C (300 degrees F) maximum operating temperature: cast
brass body, with removable piston, Teflon seat, and stainless steel spring;
straight through globe design. Valves shall be straight through pattern, with
solder-end connections.

d) Provide relief and safety refrigerant valves with forged brass bodies; nonferrous,
corrosion-resistant internal working parts; and either female threaded or brazing
connections.

e) Solenoid valves: Complete valve assembly shall be tested and designed to

conform to ARI 760. Solenoid valves shall be 121°C (250 degree F) temperature
rated, 400 psig working pressure; forged brass, with Teflon valve seat, two-way
straight through pattern, and solder end connections. Provide manual operator
to open valve. Furnish complete with NEMA 1 solenoid enclosure with 12mm (½
inch) conduit adopter, and 24 v ac, 50 Hz, normally closed holding coil.

3.3.3.12 Fittings
Wrought-copper fittings, ANSI B16.22 and ANSI B16.26, as applicable, streamlined
pattern.
A. Strainers:

a) Provide single type strainer with brass body 500 psig maximum working
pressure. Indicate direction of flow permanently on the body. Provide flange and
bolt screen cover for strainer 1 inch and larger. Screen cover for strainers
smaller than 1 inch shall be flanged and bolted or screwed.

b) Provide strainer body of a size which will provide storage area for foreign
material without contributing to excessive pressure drop. Free area of the screen
shall be minimum five times the area of the strainer inlet pipe.

c) Screen mesh size shall be not less than 80 for 25 mm (1 inch) diameter liquid
refrigerant lines, and not less than 60 for other liquid refrigerant lines. Screen
mesh size shall be not more than 40 for refrigerant suction lines.

d) Reinforce strainer screens with eight or ten wire mesh screen. Strainers may be
an integral part of the expansion valve. Braze strainer and screen joints with
silver solder.

B. Refrigerant Driers:

a) Provide solid desiccant type drier confirming to ARI 710. Driers 0.81 litre (50
cubic inches) and larger shall be cartridge refillable type, with a valve by pass of
the same size as the liquid line.

b) Provide drier body of brass, capable of holding the desiccant securely in place
and distributing the liquid refrigerant evenly throughout the desiccant, and
capable of withstanding a test pressure of 400 psi and for VRV 650 psi.

C. Moisture Indicators:

Moisture indicators shall contain material that shall indicate degree of moisture by
colour. Indicators shall be either brass, bronze, or heavily copper-plated steel.

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Locate indicating material under a bull’s-eye. Design indicators to withstand a 400

psi test pressure.
D. Sight glasses:

Provide double port, see-through type sight glass having two bulls’-eye of
nonferrous material. Design sight glass to withstand a 400 psi test pressure. Sight
glass body shall be either forged brass or bronze, with flanged fittings as specified
for piping.

E. Expansion Valves:

Provide bronze valves, suitable for silver-soldered joints, and of external equalizer
design, confirming with ARI 750, as applicable. Provide valve capillary tubes of
lengths required and distributor with side connection for hot gas bypass line.
F. Hot Gas Bypass Valve:

Provide adjustable type, sized to provide capacity reduction beyond the last step of
compressor unloading; and wrought copper fittings for solder and connections.
G. Vibration Eliminators:

Provide flexible bellows tube type vibration eliminators with seamless tin bronze or
stainless steel core. Provide with the following features and services: high tensile
bronze braid covering, solder connections, pressure tested, dehydrated, minimum
500 psig working pressure, UL-labelled, minimum 7 inch in length.

3.3.4 Pipe Installation

3.3.4.1 Pipe Work Installation Generally

A. Chilled water pipe installation

Provide automatic air vents at all high points on piping mains for chilled water
systems.
Arrange all runs of piping to prevent interference and to achieve a satisfactory and
workman like installation of neat appearance. Run all piping parallel to walls. All
valves controls, equipment, expansion compensators, flexible connections, as far
possible, all piping shall be easily accessible for inspection, maintenance and
operation.
Unless otherwise specified or instructed on site, all pipe work shall have a minimum
clearance of 25 mm between its finished face (including insulation) and the finished
face of any wall, pipe or other surface.
Where pipe work passes through walls, floors or partitions etc., mild steel sleeves
with sufficient diameter shall be provided to allow the pipe work and its insulation to
pass through uninterrupted.
Provide adequate allowance for expansion and contraction of piping by providing
expansion joints.
Install drain valves at all low points for draining and locate where easily accessible.
Threaded joints shall be carefully reamed and jointed with compound on the male
thread only. Re-tighten flanged connections after the installation has been brought

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up to its service temperature, after which operation, the insulation may be applied.
Take care not to over stress the material during construction.
Inaccessible pipes in chases, ducts, partitions and, where no easy access is
available, shall be welded irrespective of size. No joints shall be made in walls or
floors, etc.
Provide strainers upstream of each pump suction and inlet of equipment.
Provide gate, globe, and check valves in all piping systems as required for
satisfactory operation and control of equipment. Provide shut-off valves wherever
piping is connected to any equipment.
Pressure gauges shall be installed on the suction connection & delivery of each
pump and in the feed and pressurization line to each system.
Condensate drains shall be provided to all equipment requiring same and shall be
routed, via a trap, to the nearest waste stack or floor drain as appropriate.
Discharge condensate drain indirectly to waste.
All ends shall be cut square and be well reamed or filed to ensure that the full bore
of the pipe is maintained.
Where branches are to be welded in, the ends of the branch pipes shall be
correctly shaped to the main pipe and the hole for the branch pipe cut in the main
shall be the full diameter of the branch pipe and shall be executed with the aid of a
template. All loose scale and oxide shall be removed from the inside of the main
pipe before the branch boss is welded into position.
Pipe welding operations shall be performed by welders holding a certificate from
the inspection agency for the class of piping to be welded. No superfluous material
shall restrict the internal opening of pipes and fittings.
When welding or cutting with a torch, take precautions to prevent fire.
Arrange piping to permit ease of equipment removal. Flanges or unions shall be
provided on all pipe connections to each piece of equipment. Install all valves in
equipment rooms in accessible locations from the floor.
Where ASTM are specified pipes shall have same specification as standards
indicated (BS) and contractor shall ensure that alternative standard submitted is
equivalent to the specified standard. All BS products shall carry kite mark seal.
Special care shall be taken to prevent the ingress of dirt or rubbish entering the
open ends of all pipe work during erection. Approved caps shall be used for this
purpose, the use of shavings, rags or paper will not be allowed.

All pipe work shall be tested to at least one and a half times the working pressure
of the systems. If any leaks be detected during the specified testing, the defective
portion of the weld shall be cut out and re-welded, and further tested until found
satisfactory.

After the chilled water pipe work system has been completed, but before the final
connections to the fan coil units/ air handling units are made, the systems shall be
continually flushed through with clean water until the discharge water is clean. To
facilitate the fan coil connections shall be isolated and temporary loops made
between the flow and return connections on the end of each run.

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B. Refrigerant pipe installation

Install refrigerant piping in accordance with ASHRAE 15.

Cut refrigerant piping accurately to measurements established at the site, and install
without springing or forcing. Installed piping shall be sufficiently flexible to allow
expansion and contraction caused by temperature fluctuation inherent in its
operation.

Do not conceal piping in walls and partitions, underground, or under a floor, except
as indicated. Do not conceal pipe joints within the building. Run insulated pipe as
indicated and as required, with sufficient clearance to permit application of insulation.
Care shall be taken to avoid interference with other piping. Run piping plumb and
straight.

Refrigerant piping shall be joined by brazing. Free the inside of tubing and fittings
from burrs and flux. Clean the parts to be jointed thoroughly with emery cloth. Heat
to a temperature greater than the solder flow point, and keep heated until the solder
has penetrated the full depth of the fitting and the extra flux has been expelled.

Joints shall be air cooled; marks and traces of flux shall be removed. Protect the
piping from forming an oxide film on the inside.

Provide slope to refrigerant pipe.

Install traps where required to entrain oil in vertical runs.

Install refrigerant driers, sight glass liquid indicators, and strainers in refrigerant
piping if not furnished by the equipment manufacturer. Installed driers in liquid lines,
with service valves and valve bypass line.

Install moisture indicators in liquid line downstream of the drier.

Locate strainers near the equipment requiring protection. Install a strainer in the
common refrigerant liquid supply to two or more thermal valves in parallel if each
thermal valves has a built-in strainer. Install strainers with screen down and in
direction of flow as indicated on strainer body.

Install refrigerant charging valve connection for each remote type refrigeration
system, located on the reducing outlet of a full size tee in the liquid line, upstream
from the refrigerant drier and liquid indicator sight glass.

Install solenoid valves in horizontal lines, locate stems vertically, and indicate
direction of flow on the valves.

3.3.4.2 Pipe work Support

All hangers, supports, anchors, and guides shall be in accordance with the British
Standard BS 3974 or other equivalent and approved International Standards.

3.3.4.3 Horizontal Piping

Provide one of the following types of hangers for horizontal piping manufactured by
one of the approved makes.
a) Provide clevis type supports. Keep the clevis nut outside the insulation.

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b) Where pipe exceeds maximum loading recommended for clevis type hangers,
furnish steel pipe clamps.
c) For pipes 200 mm and larger, and where provision for expansion and contraction is
required, provide single pipe-roll support with two rods and adjustable sockets, or
for pipe 150 mm and smaller, adjustable swivel pipe-roll with one rod.
d) Provide trapeze hangers where several pipes can be installed parallel and at the
same level, and fabricate from structural steel shapes. Use roller chairs or pipe-roll
stands where provision for expansion is required.
i) Spacing shall not be farther than the closest interval required for any size pipe
supported thereby, or as necessary to prevent damage or failure to the
structure.
ii) Where there is doubt of the structural capacity for concentrated loads
necessary structural calculations shall be carried out and the load distributed
sufficiently.
e) Floor Supports: Contractor to fabricate galvanised steel frame to suit the site
conditions to the Company’s approval.
f) Horizontal Piping Support Schedule
Support horizontal piping on threaded, galvanised, hot rolled steel rod hangers.
Where proprietary hangers are being used, the threaded rod size shall be as
required for the hanger. The maximum spacing shall be based on the load carrying
capacity of the hanger, after allowing a safety factory of 50% on the insulated full
pipe weights.
Maximum Spacing between Single Pipe Supports:
Nominal Pipe Size, mm

15 20 25 32 40 50 65 80 100 125 150 200 250

Maximum Span Metres
1.5 1.8 2.1 2.1 2.7 3.0 3.4 3.7 4.3 4.9 5.1 5.8 6.1

Minimum Rod Diameter, Millimetres

6.4 6.4 9.5 9.5 9.5 95 13 13 16 16 16 19 24

Support steel piping 300 mm and larger at 6 m intervals or less to ensure even
distribution of loading on structural members.

3.3.4.4 Vertical Piping Supports:

Vertical pipe supports shall be steel extension pipe-clamps/Riser clamp.
Manufacturer's rated maximum loading for each size pipe shall be used (with
minimum 50% safety factor) for spacing of supports. Bolt clamp securely to pipe,
reset clamp-end extension on building structure.

Inserts and Expansion bolts:

a) Furnish and set inserts in concrete forms.

b) Concrete inserts shall be as follows: Black malleable iron universal type for
threaded connections with lateral adjustment for pipe sizes up to 200mm.

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c) For pipes 200 mm and over or equivalent group of pipes on trapeze, use two
or more inserts to prevent exceeding maximum loading.

d) As an alternative to the above mentioned inserts the Contractor may use

expansion bolts. If the Contractor uses expansion bolts, the maximum
spacing between supports may need to be reduced so as not to exceed the
maximum loading and the expansion bolt locations shall be determined in
coordination with the structural elements.

3.3.4.5 Support Insulators

The Contractor shall provide moulded hard rubber insulators at all supports of
insulated pipe work to transmit pipe load to hangers (or supports) without crushing
the insulation. The rubber density shall not be less than 1100 kg/m3 and operating
temperature range shall be -20 deg C to 110 deg C. The thickness of insulators
shall be same as the insulation, and vapour barrier shall be continuous across the
outside of the insulators.
Unless otherwise indicated, all supports, clamps or frames shall be protected against
corrosion by either galvanising or two coats of suitable primer with two coats of
approved epoxy paint. All Supports/clamps or frames used shall be hot dip
galvanised.

3.3.4.6 Trenches
Buried chilled water pipe work shall be laid on minimum 150 mm thick compacted
bedding and shall have a minimum cover of 800 mm. Backfilling shall be in 150mm
thick layers, the first layer being laid by hand.
Bedding and backfill shall comprise of sand, excluding stones retained in a 25 mm
sieve, or other material equal and approved by the Company. Watering shall be
minimal, sufficient to dampen but not to flood. All buried chilled water lines shall be
provided with protection jacket as well as normal insulation and Cora cloth with paint.

3.3.4.7 Refrigerant Pipe Work

Pipe work shall be installed neatly and shall be supported in the following manner.
General

Pipe work shall not be directly buried but be enclosed in pre-formed, unfilled ducts,
and sealed at building entry. In cases where proprietary metal clamps are used,
pipe work shall be insulated, using plastic tape, to prevent chafing and electrolytic
action.

Each refrigeration circuit shall be supplied with a correctly sized thermostatic

expansion valve, liquid line solenoid valve with suitable coil, liquid line sight glass
and moisture indicator, and open able filter drier with shut-off valve. Refrigeration
pipes shall be protected by metal cladding (0.55mm) after insulation. Refrigeration
pipes shall run in Company’s approved a galvanized steel tray. Provide copper
finished steel clamp or plastic coated steel clamp or Company’s approved.

Vertical runs

Pipe work shall be clamped using hard wood clamping blocks or, subject to approval
by the Company, proprietary pipe work fixings. The maximum distance between
clamps shall be 1000mm and the minimum distance from a bend to a clamp shall be
300 mm.

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Horizontal Runs

Pipe work shall be laid level without sagging, and supported by hard wood battens,
or proprietary fixings, and clamped. The maximum distance between clamps shall
be 1000 mm and the minimum distance from a bend to a clamp shall be 300 mm.

3.3.4.8 Condensate Drains Pipe Work

Pipe work shall be laid to fall, without sagging, and shall include provision for clean
out of all sections.

Drain sizes shall not be less than the equipment drain pan connection size and shall
include a union, or similar, coupling located so that the equipment may be removed.

Traps shall be provided to ensure that a seal is always maintained from the drainage
system and between air-conditioned spaces. Traps shall be located to avoid drying
out. For this reason, condensate drain discharge should be above wash hand basin
traps, or similar.

3.3.5 Pipe Insulation

3.3.5.1 Chilled Water Pipe Insulation

Chilled water pipes other than pre-insulated pipes shall be generally insulated with
rigid pipe sections of aluminium foil faced glass fibre insulation with density of 65
Kg/m3 having a thermal conductivity factor of 0.034 w/m.k at 10 deg. C. Self-
adhesive aluminium foils shall be used to fasten joints.
Internal chilled water pipes (inside buildings) shall be insulated by 40mm thick rigid
insulation for pipes up to 40mm diameter and 50mm for pipe sizes 50mm diameter
and above.
External chilled water pipes shall be insulated by 50 mm thick rigid insulation for pipe
sizes up to 40 mm diameter and 75 mm for 50mm diameter and above.
For both internal and external pipes the insulation shall be finished with a water proof
20x20 (thread/inch) woven glass cloth cover painted with two coats of approved anti
fungal lagging adhesive. Rubber half sectional inserts shall be used where the
support clamps are fixed.
Exposed chilled water pipe-work insulation on roof, plant room and other areas shall
be provided with aluminium cladding. It shall be clad using an outer covering of plain
aluminium sheet of 0.55mm or thicker.

3.3.5.2 Refrigerant Pipe-Work Insulation

Refrigerant pipe-work shall be insulated with aluminium foil faced glass fibre
insulation, 50mm thick with metal cladding.

3.3.5.3 Condensate Drain Pipe-Work Insulation

Condensate drain pipe-works shall be insulated with flexible 25mm thick fibre glass
of 24 kg/M3 density and shall be wrapped with cotton canvas cloth of 200 g/m2(8oz
density). Metal cladding shall be used for drain pipe.

3.3.6 Execution
Insulation on pipes and ducts shall not be applied without adequate application of
adhesives on the pipe/duct surfaces.

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Insulate and finish valves and fittings in the same manner and same thickness as piping
in which such items are installed. Moulded, factory shaped sectional pipe covering,
factory- or job fabricated may be used subject to satisfactory visual checking by the
Company.

Particular attention shall be paid to the finished appearance of all thermal insulation
which must present a neat and symmetrical appearance running true in line with pipe
layouts, etc.
Direct contact between pipe and hanger shall be avoided. Hangers shall pass outside
of the sheet metal protection saddle, which shall cover a section of high density
insulation, of sufficient length to support the pipe without crushing the insulation. The
vapour barrier shall be lapped over the saddle and securely cemented to it. Minimum
thickness of metal saddle is 1.5 mm. The insulation shall be installed in accordance with
the manufacturer’s printed instructions.

3.3.7 Pre-insulated Chilled Water Pipes

All below grade chilled water lines shall be pre insulated unless specified otherwise. The
system shall be non-corrosive, structurally strong, completely water proof and entirely
resistant to attacks by salts, water and all ground chemicals normally encountered in an
underground environment. The system manufacturer shall have fabricated systems of
the composition defined hereinafter for at least five years. All straight section, fittings,
anchors, end seals and other accessories shall be factory prefabricated to job
dimensions, and designed to minimize the number of field welds. The system design
shall be in strict conformance with ASME B 31.1, Latest Edition. Pipe movement due to
thermal expansion or contraction shall be accommodated with expansion loops or
elbows. The system manufacturer shall supply an integrated leak detection/location
system factory installed within the piping system as described herein.
The complete system shall be computer analyzed by the pre-insulated piping system
manufacturer to determine stress and anticipated thermal movement of the service pipe.
i) Service Pipe

Internal piping shall be seamless black Mild steel, heavy weight to BS EN10255 or
equivalent with to ASTM A53 Schedule 40. All joints shall be butt welded for sizes 65mm
and larger and socket welded for 50mm and below. Straight sections, shall be supplied
in 12M random length where it possible.
ii) Insulation

The pipe insulation shall be rigid polyurethane foam conforming to ASTM C 591, with a
nominal density of 48 Kg/M3. The insulation shall completely fill the annular air space
between the pipe and the jacket. Support guides shall be factory installed to assure
equal thickness of insulation around the pipe.
Insulation thickness shall be as follows:
Pipe size
Diameter
in mm Up to 25 32-40 50-80 100-200 Above
200
Insulation 25 40 50 65 80
thickness

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iii) Leak Detection/Location

The leak detection cable shall be factory installed and supplied by the prefabricated
system manufacturer. The leak detection/location system shall consist of
microprocessor based monitoring unit(s) capable of continuous monitoring of a sensor
string for leaks/faults. The units shall have a sensing range of 610meter to 1525 meter
(2000) (5000) feet per cable. The alarm unit(s) shall operate on the principle of pulsed
energy reflection and be capable of mapping the entire length of the sensor cable and
storing the digitized system map in non-volatile memory. An analogue system using
an alarm threshold value, fixed for the length of the cable, or a portion of the cable, will
not be allowed as it will not detect a second leak smaller than any acknowledged leak.
The alarm unit(s) shall provide continuous indication that the sensor cable is being
monitored.
After proper acknowledgement of a minor leak, the leak detection/location system shall
be capable of monitoring the entire sensing string for additional leaks even if they are
smaller than the leaks previously acknowledged. The system shall be capable of
accounting for minor installation irregularities, static moisture and puddles (such as
condensation) with no loss in accuracy or sensitivity. The system shall locate the point
of origin of the first leak or fault within ±1.5 metre (±5 feet), whichever is greater. The
monitoring unit shall report and record, to non-volatile memory, the type of fault,
distance, date, and time of an alarm.
The system manufacturer shall have at least seven years of experience with leak
detection/location sensor cable technology and provide a factory trained
representative at two on-site meetings for pre-construction and sensor/electronics
installation.
The system shall have multi-level security passwords for access to operating functions
with recording of all password entries to non-volatile memory.
The alarm unit(s) shall be enclosed in a modified NEMA 12 enclosure and have a two
line by forty character display providing status and alarm data. The monitoring unit(s)
(will be field connected to any) (will have a factory mounted) alarm horn. The
monitoring unit shall be U.L. listed and FM approved to provide connections for
intrinsically safe sensor circuits for use in Class 1 Division 1, Groups C and D
hazardous locations.
The system shall be tested and found to comply with the limits for a Class A digital
device, pursuant to Part 15 of the FCC rules and so labelled.
The system shall be evaluated by an independent third party according to the Third
Party Procedures developed according to the U.S. EPA’s “Standard Test Procedure
for Evaluating Leak Detection Methods: Liquid-Phase Out-of-Tank Product Detectors.”
The evaluation results shall verify the system manufacturer’s claims regarding
sensitivity, range, and other performance data.
Ability to locate a leak shall not depend on battery backed-up functions. In the event of
power failure, system conditions and parameters shall be stored in non-volatile
memory allowing the units to automatically resume monitoring, without resetting, upon
restoration of power.
The monitoring unit(s) power requirements shall be 240V, 50 Hz, single phase.
Monitoring units shall be equipped with an RS-232 communication port and a
minimum of two SPDT output relay, rated for 250 VAC, 10 amps.
The sensor cable, connectors, (probes) and jumpers shall be supplied by the
manufacturer of the monitoring unit(s). The cable sensing principal shall provide for
continuous monitoring while short lengths of the cable are in contact with liquids,
without altering the systems sensitivity and/or accuracy.
Software shall be provided that allows the user to remotely or on site interface thru the
RS-232 serial port for trouble shooting and diagnostics. Software shall have the ability

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to operate the PAL-AT monitoring units and retrieve each of the stored reference maps
and current condition TDR traces. Software shall also be including the above features
and also having auto call and continuous monitoring. The auto call will allow the PAL-
AT, thru PALCOM software to call a designated phone number and deliver a verbal
message when an event is detected.
iv) Protective Jacket

The outer casing protective jacket shall be high density polyethylene (HDPE) industrial
grade material and shall conform to ASTM D 1248, Type 3, Class C specifications.
PVC, or tape materials shall not be allowed as material for the jacket construction.
The jacket shall be seamless throughout. All fittings shall be factory welded, by butt
fusion or extrusion welding process. Hot air welding or taping shall not be allowed in
the factory or in the field.
v) Anchors, End Seals, Gland seals and other accessories

All system accessories shall be factory manufactured water tight and designed to
prevent moisture from entering the insulated system.

3.3.8 Chilled Water Pumps

The chilled water circulation pump must be selected (duty & stand by) for the system
head and flow requirements. Pumps and motors shall be capable of operating at
system pressures 25% above the design pressure for the required water volume.
The pump manufacturer shall provide dedicated performance curves indicating the
point of operation and maximum duty with the selected drive configuration.
Chilled water circulation pumps construction shall be end-suction, centrifugal, direct
drive units, with cast iron casings, bronze/ stainless steel impellers, stainless steel
shafts, mechanical seals and flexibly close-coupled drives to totally enclosed fan
cooled, class F insulation, industrially silent, three-phase motor with speed not
exceeding 1500 rpm. The design shall allow back pull out servicing; enable the
complete rotating assembly to be removed without disturbing the casing piping
connections.

Pumps shall be supplied with flanged connections to BS 4505 together with mating
flanges. Pump flanges shall be tapped for discharge and suction pressure/altitude
gauges.
The pumps shall be entirely suitable for continuous operation in ambient
temperatures of 60°C and in open space.

The pump and motor shall be aligned and shall be mounted on a manufacturer
fabricated cast iron steel base and the complete unit shall be with anti-vibration
appropriate spring mounted on a minimum150mm thick reinforced concrete plinth
with 50mm thick layer of dense cork or other approved anti-vibration media
surrounded by kerb and sealed with bituminous compound to prevent ingress of
moisture.

Each pump shall be fitted with rubber sphere type vibration isolations on suction and
delivery pipe work connection. These shall be supplied an approved manufacturer.

Suction connections shall include isolating valve, strainer, pressure gauge and cock,
drain cock and flexible connection. Delivery connection shall include isolating valve,
check valve if the pump is in parallel connection, pressure gauge and cock, and
flexible connection. Gland drip, if any, shall be piped to waste.

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The chillers pumps shall operate on a duty/standby basis, with automatic

changeover in the event of pump failure, or to arrange equal operation time for
each pump. Each pump shall have hours run meter in the HVAC control panel.

3.3.9 Pre-commissioning Cleaning Of Pipe Work

The Contractor shall carry out through cleaning of the entire chilled water pipe work
system, and shall allow for the following procedure.

Fill the system with fresh water and add recognized approved cleaner (chemical)
sufficient quantities as recommended by the supplier taking necessary samples
during each flushing. Operate the system for at least six hours taking samples for
analysis every two hours. Temporary pumps shall be provided for this purpose, as
required.

Thoroughly flush the system for as many times as necessary to remove all traces of
pre operational cleaning chemical and as.

Recommended by the supplier taking necessary sample for analysis during each
flushing.

Refill the system with fresh water and add oxygen scavenger and corrosion inhibitor
in adequate quantities as recommended by the manufacturer, to suit the overall
system volume.

The Contractor shall follow the written instructions of the manufacturer for the mixing
of all chemicals and a copy of these shall be kept on site.

3.3.10 Chilled Water Pressurisation Units

The unit shall comprise expansion and makeup tank, water connections with isolating
valve and float valve, centrifugal pumps (duty/standby) with continuously rated single
phase motor, pressure switch, pressure reducing valve with gauges, interconnecting
pipe work and valves, all mounted on to a mild steel base plate and concrete plinth.
Cold water make-up connection shall have control and isolating valves, check valves
and water meter to check volume of make-up.
Connection to the chilled water system shall be via an air separator and automatic
air vents shall be provided at high points of the system. In addition to this, the unit
shall the following:
 Test “button”

 System isolating valve to enable commissioning of the set prior to opening the
system.

 Multi-volt transformer to provide the necessary signal voltages.

 Pressure transducer and lead.

 All necessary interconnecting pipe work in high gauge copper to BS 2871,

Table X and non return valves etc.,

 Two pumps operating on a duty/standby basis.

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The entire system shall be controlled by a microprocessor with LCD Screen which
must give alternate pumps starting on two pump sets, pump start frequency/leakage
detection alarm to indicate a leak causing too many starts per hour, thus damaging the
switchgear etc., high and low pressure alarms manually set, a common alarm to shut
down the system if the pressure limits are transgressed, indication of transducer or
transducer lead faults.
Volt free contacts must be provided for the following:
Common system alarm and system OK status, high pressure alarm, low pressure
danger alarm, pump start frequency. These volt free contacts for connection to a future
BMS. System expansion vessel(s) to be steel “water in bag” type of correct size to suit
system parameters which an air cushion pressure to match “initial system pressure”.
This vessel shall be mounted external to enclosure.
Expansion Tank: The expansion tank shall be sized to suit the system water quantity
unless a larger size is required for proper functioning of the system.
The tank shall be fabricated from mild steel and shall be painted both inside and out
after completion of welding. The tank shall be rated for operation at 16 Bar NP in
accordance with the pressure test requirements of ASME or approved equal.
The tank shall have a neoprene rubber diaphragm rated for continuous operation at 16
Bar NP.
The tank shall be complete with all tapings for inlet (which may also be the drain,) air
recharge, and pressure relief.
A spare diaphragm shall be maintained by the Contractor at site during the warranty
period and shall be handed over to the Owner in “as new” condition at the end of the
warranty period.
Installation shall be in accordance with the Manufacturer's recommendations.

3.3.11 Chemical Dosing

Chilled water treatment should be by integral makeup tank dosing system, or by
dosing pot, for the following.
 De-scaling
 Corrosion inhibition
• Algae inhibition

The method of introducing these chemicals into the system shall be by means of
automatic dosing system. 2 x 100% dosing pumps shall be provided. Digital
controller with all sensors shall be used.

3.3.11.1Chemical Dosing Procedure

Before treatment, the complete chilled water system shall be flushed to the approval
of the Company and a final leakage test performed. Large bore (minimum 50mm)
flush points, at lowest sections of the system, shall be provided.
The system shall then be dosed with a de-scaling agent and left for a minimum of 24
hours.
The system shall then be drained down, re-flushed, re-filled and dosed with a
corrosion inhibitor and an algae inhibitor.
Table-chemical dosing below gives details for treatment subject to Company written
approval.

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Table - Chemical Dosing

Treatment Dosage
De scaling 5 litres per 1 m3 of system volume
Anti-corrosion 10 litres per 1 m3 of system volume
Algae 1 litre per 10 m3 of system volume

3.4 Air handling system

3.4.1 Air Handling Units

3.4.1.1 General
Air handling units shall be draw through type; manufacturers of air handling units shall
have ISO 9001 certification, and performance of the unit shall be EUROVENT
certified. Provide as a complete system. Units shall be provided with vibration
isolation.

3.4.1.2 Components
Air handling units shall consist of the minimum following components:
Casing
Motor(s)
Fan
Filters, including one or more of the following, Pre-filters, medium efficiency filters,
and final filters
Cooling coils / chilled water or direct expansion (DX). The AHU cooling coil shall be
made of copper-copper in all PDO application.
Electrical heater (thyristor type)
Volume control damper (VCD), Motorised damper (MD), none return damper
Sand trap louver with pre filter and VCD
Door safety limit switch shall be interlinked with DDC.
Internal inspection light with ON-OFF switch and with viewing provision (made of
hard plastic). Fan chamber 2 no’s; filter chamber 1 no; cooling coil chamber 1 no.
Mixing box Section with dampers
Humidifier /Dehumidifier: (if specified)
Heat recovery system: (if specified)
Weather hood, if unit install outside/open area: (if specified)
Moisture Eliminators.

3.4.1.3 Casing
Air handling units shall be packaged, factory assembled units constructed from
modular, double skinned panel and insulated throughout with minimum 40kg/m³
polyurethane injected foam to a thickness of 50mm., , which provides an overall
thermal conductivity, k = 0.017 W/MºK incombustible with class of in flammability, all
mounted on a hot dip galvanised steel base frame. Casing shall be designed for
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indoor/out-door installation. Sheet metal thickness shall be not less than 0.7MM for
the inner skin and 0.7MM for the outer skin and made from zincates steel sheets.
Inside and outside of panel walls shall be completely smooth.
Service doors shall be provided with special gasket and locking device. A factory
mounted, weather resistance (enclosed and gasketed), vapour- tight incandescent
light fixture shall be provided for access and/or fan module. The fixture shall be
complete with junction box, globe, aluminium globe guard, receptacle, and bulb.
Access doors shall be provided with aluminium hinges with quick release latches
having external and internal handles for external and internal opening.

The inspection side of the coil section panels shall be assembled with bolts and nuts
for easy removal of coils. Panel air tightness and sections up to 2500 Pa as required
in EUROVENT 2/2.
The AHU manufacturer shall guarantee that no condensation shall take place on the
exterior of panels. In the event that any condensation problems appear after
installation, the Contractor shall undertake all remedial measures to rectify and to the
satisfaction of the Owner. Any stacked or double height coils shall have separate
drain pans to reduce carry over such pans will be piped to the main drain, not into the
lower pan.

3.4.1.4 Fan and Motor

Fans shall be double inlet double width, centrifugal fan with casing made of galvanized
sheet metal, statically and dynamically balanced. Fans shall be with aerofoil shaped
blades. Motor and fan assembly shall be mounted on a common galvanized steel
base frame with easily adjustable motor slide rail. The unit shall have internal vibration
isolation system by mounting fan, motor and drive assembly on spring isolators. Fan
shall be driven by at least two V-belt arrangements and adjustable pitch pulley. All
fans shall be selected for maximum efficiency and in no case less than 75 percent.
Fan shaft shall be made of carbon steel C45, machined and polished, and bearing
shall be self-aligning. The bearing is lubricated for life and maintenance free. The
bearing shall be selected for life of 200,000 Hours operation (fan manufacturer shall
certify that the bearing selected for the particular duty shall be theoretically suitable for
this duration of operation). Fan drive shall be rated at 150% of the maximum motor
power of the units and shall be fitted with adjustable belt tension arrangement.
The fans shall be licensed to bear the AMCA air and sound certified rating seals.
Motors shall be totally encased, foot mounted, fan cooled, IP55 with Class 'F'
insulation. Motors shall have a power operating margin of not less than 25%. The
outlet air velocity shall not exceed 12 m/s. Fans and shafts shall operate well below
their critical speeds. The fan discharge shall be connected to the air handling unit
casing through canvas connection to prevent vibration transfer. The fan belt shall be
covered by security guard all around. The construction of guard shall be in two half’s
and the top half shall have access door for checking the belt tension. The guard shall
be covering both sides (fan &motor).The locking mechanism shall be agreed by the
PDO HVAC Engineer. The guard shall be epoxy coated and red painted to furnish the
unit.
The AHU shall be provided with factory installed emergency switch mounted in the
channel close to the door of fan chamber.
If any out of balance is apparent on site the Company reserves the right to require new
factory supplied units to be provided until satisfactory balance is demonstrated.

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3.4.1.5 Cooling Coil (Chilled Water & DX type)

The cooling coils shall be designed for use with chilled water and the selection of the
circuiting arrangement and fin spacing shall be optimum to meet the required load
and dehumidified requirements.
Cooling coils shall be constructed of seamless copper pipe mechanically expanded
onto copper fins. Tube thickness shall not be less than 0.45 mm. Fin thickness shall
not be less than 0.24 mm, with 10- 14 fins/inch fin spacing.
The coil shall be assembled in a galvanized steel housing, the use of dissimilar
metals in the construction, where likely to cause galvanic corrosion shall be avoided.
The coils shall be mounted on slide tracks to be removable from the side. Coil
connections shall be arranged so as to enable same side connections to the flow
and return pipe work, and to have the supply and return connections to headers to
give counter flow of air and water. Equal flow of water shall be through all the tubes
in the coils.
Headers shall be heavy section seamless copper tubing with connections made in
steel pipe with anti-corrosion protection paint and with external screw thread.
The coil shall be designed to operate at 16 bar NP, Air face velocities shall not
exceed 2.5 m/s, there being no carryover of Condensate water and water tube
velocities shall not exceed 2.4 m/s. Condensate drains shall have a deep seal trap,
with minimum depth of 75 mm, which can often affect the height of the concrete
support base for the AHU.
Where coil connection protrude through the casing and gape between casing and
coil that opening shall be suitably sealed with the grommets or gasket IP 65.
Drain pans shall be stainless steel; slope at one sided placed under the all cooling coil
within the coil section and will extend underneath the headers and beyond the fin block
to ensure adequate collection of condensate. The drain pans outlet shall be located at
the lowest point(s) of the pan Drain pans shall have drain connection to the service
side. Provide drain connection made of same material as drain pan. Do not use
dissimilar metals because of the risk of galvanic corrosion. Weld connection to the
drain pan, minimum size 38mm and outer threaded. Insulate and metal clad to drain
line up to the soak pit.

Cooling coils performance shall be rated and certified to ARI 410 Standards. Coil shall
be air pressure tested in factory to a minimum pressure of 24 bars and DX type 32
bars.

3.4.1.6 Moisture Eliminators

Moisture eliminators with a minimum water separation efficiency of 99.9 % shall be
provided on the downstream face of all cooling coils in air-handling units.
The moisture eliminator shall be made completely of stainless steel sheet including
separate drip pan made of stainless steel and installation frame.
The AHU drain pan shall be connected to floor drain through an open-able type U-Trap
with union fitting, a funnel and a connecting pipe made of copper altogether, minimum
size 40 mm (DN 40) connected to the next floor drain. The U Trap shall be designed
for a water level according to the relevant air pressure differential and in consideration
of additional 50 mm W.G. for reserve.

3.4.1.7 Electrical Heaters

Electric air heaters shall consist of a number of sheathed heating elements of the
enclosed type mounted in a sheet steel casing. Electric heating elements shall be 80

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% nickel, 20 % chromium resistance coils, Casing shall be made of the same

material as air handling unit.
Electrical heaters shall be provided with terminal box, pre-wired electrical
components, suitable for controls/safety and devices such as disconnecting switch,
multistage control or theyristor (SCR) control, relays for remote alarms, manual reset
high temperature safety cut-out, voltage control protection, sequence relay
protection, ear -thing clamp on the casing and bolt in the terminal box for connection
of ear-thing cables.
The surface temperature of the elements shall not exceed 400ºC when measured in
an air flow of 2.5 m/s. A high temperature limit cut-out device with hand reset button
shall be incorporated such that the limit device sensor is nearest to and above the
heating elements which are energized by the first control step. The device shall
operate within two minutes at a temperature of 68.5ºC.
An airflow switch shall be provided to switch off the electrical heater in case of
ventilation air shortage to avoid overheating. The flow switch shall have an automatic
reset.
The control of electric air heaters shall be interlocked with the fan motor starters and
an air flow control of the pressure or sail switch type so that the heaters cannot
operate unless the fan is running.
The number of elements in the heater shall be the same as or a multiple of the
number of steps in the controller. All heaters and heater sections of more than 3 kW
loading shall be balanced over 3 phases and the complete heater bank shall be
arranged for balanced operation on a 3-phase 4-wire system.
The connections from each element shall be taken to a readily accessible terminal
box arranged for conduit entry. Each heater section shall be separately fused and
the neutral point of all 3-phase star-connected sections shall be brought out to a link
in the terminal box. The terminal box for the heater shall be independent from the
terminal box for supply fan motor. Both boxes shall be fixed on the wall of the AHU
with IP rating of 65 regardless of the location (indoor or outdoor) of the AHU. Near
hot areas the wiring insulation shall be of a quality suitable for the maximum working
temperature.

3.4.1. 8 Humidifiers
Humidifiers shall be jacketed dry steam units that provide full separation from steam
ahead of the jacketed control valve.
Humidifiers shall introduce steam directly into the air stream through a jacketed
manifold that prevents condensate from being introduced into the air stream.
Humidifiers shall be supplied with a cast iron in-line strainer and a cast iron float and
thermostatic or inverted bucket steam trap. The strainer shall have a no-crush
screen.
Humidifier shall have cast iron or stainless steel separator to receive steam at
operating pressure and remove water droplets and particles when operating at
maximum capacity. The separator shall be located ahead of the control valve.
A drip leg shall be supplied with the separator and shall be sized according to steam
capacity. The drip shall be at the bottom of the separator, located ahead of the
stream trap. The control valve shall be stainless steel, steam jacketed, with a
parabolic plug. The control valve shall be capable of modulating flow over entire
stroke. The control valve operator shall stroke valve over entire range and shall be
capable of tight shutoff at the maximum pressure.
Humidifier shall be supplied with internal drying and silencing chambers, jacketed by
steam, at atmospheric pressure. The silencing medium shall be stainless steel.

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A drain pan shall be constructed of 316 grade stainless steel for lifetime duty.
Condensate from the steam distributor shall be flowing to the drain pan. It should
house the steam generating canister and incorporate an emergency overflow to
protect against water spillage out of the cabinet. A removable drain plug shall allow
manual draining of the pan before servicing. The drain pan shall be removable for
maintenance and allow access to the internal components.
Distribution manifolds shall be stainless steel, steam jacketed. The manifold shall be
provided with stainless steel silencing screen over entire length. The manifold jacket
shall allow condensate to return to the trap.

3.4.1.9 Mixing Box

Unit shall be provided with a mixing box. The mixing box shall include integral
outside and return air damper. Outside air shall enter through the outside air hood.
The outside air hood shall complete with rain lip and bird screen made of aluminium.
Outside and return air dampers shall be linked together and sized to handle 100% of
the supply air volume.
Damper shall be double skin, opposed blades, with motor or manual controlled link
rod. The damper blades shall be fabricated of aluminium and continuous
Thermoplastic Elastomer (TPE) seals are inserted onto every damper blade. The
rotated rod of handle is made of brass and handle is fabricated of aluminium casting.
Dampers shall be the ultra-low leakage type.

3.4.1.10 Filter
The filter section shall be supplied with the same casing construction as the air
handling unit. The filters shall be arranged in banks in sufficient numbers to operate
at the correct manufacturer’s rating, and shall be supported in a suitable aluminium
holding frame. Filter materials shall fire resistant in accordance with the
requirements of BS 9999. The filter housing design shall be such that it allows
speedy removal and replacement of the filter media.
Aluminium Sand trap louver shall be provided for fresh air intake system with the
sand trap louver and damper.
Panel filters and bag filters shall be provided to each air handling unit. Pressure
switch with adjustable setting shall be provided for each type of filter with
independent pressure switch. Each switch shall be connected to the plastic pipe
(heavy duty type) through aluminium elbows fixed in the AHU body. The elbows shall
be leak free.

a) Panel Filter:

This type of filter shall be constructed of aluminium to withstand washing by water.

The filter panel shall be constructed from multiple layers of expanded aluminium
mesh or glass, natural or synthetic fibre, with the layers being corrugated or plain
and arranged alternately at right angle at one another. Filter media shall be
supported on both sides with rigid and thicker aluminium expanded metal mesh.

Filters shall be 50 mm thick with a rolled or extruded aluminium frame. The frame
section shall be ribbed for stiffness and its inner edges treated to prevent sharpness
and increase strength. Corners shall be mired and riveted where it is necessary.
Folding handles shall be applied to the short side of all washable filter panels for
easy removal and cleaning. The filter support frame shall be suitable for the
installation of either side.

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It shall have the minimum average synthetic dust weight arrestance by EUROVENT
4/5 (i.e. Grade EU3) /ASHRAE Standard 52.1 – 1992 and maximum initial
resistance at 2.5 m/s face velocity. The filter shall operate to 150 Pa final resistances
for 50 mm thick panels shall be as below table.

Table 3.4 - (1) Resistance of washable panel filter

Thickness Average Arrestance Initial Resistance

50mm 60% 45Pa

Filtration media shall be coated, each layer of expanded aluminium shall be

furnished with a flame resistant filter coating before assembly into a pack. The
adhesive shall have a flash point exceeding 1800C.

Performance data for expanded aluminium filter panels oiled with a thixatropic
adhesive shall have the following minimum average synthetic dust weight arrestance
by EUROVENT 4/5 (i.e. Grade EU3) ASHRAE Standard 52.1 - 1992; minimum dust
hold capacity and maximum initial resistance at 2.5 m/s face velocity.

Table 3.4-(2) Dust hold capacity and resistance of washable panel filters

Thickness Average Dust Hold Initial

Arrestance Resistance

50mm 70% 1600g/m2 50Pa

b) Bag Filter:

The air filter shall be of high efficiency, extended area, deep pleated, disposable
type. The media shall be micro fine glass fibre, which is reinforced by a laminated
synthetic backing. It shall have a nominal width of 600 mm and the following average
atmospheric dust-spot efficiency by to EUROVENT 4/5 (i.e. Grade EU7) /ASHRAE
Standard 52.1 – 1992 and initial resistance at 2.5 m/s face velocity. The air filter
shall be designed for the air velocity of 1.0 to 3.5 m/s and shall operate to 250 Pa
final resistance.

Table 3.4-(3) Resistance of Bag Filter

Average Efficiency Initial Resistance Not

Not Exceeding
Less Than
65 % 75 Pa
85 % 100 Pa
95 % 145 Pa

The filter package shall be factory assembled as a complete set readily for site
installation. The filter assembly shall consist of a holding frame, sealer frame, media
retainer, and the disposable element.

The sealer frame shall be constructed of galvanized steel of sufficient thickness and
be equipped with suitable airtight sealing gasket and sealing mechanism on the
sealer frame flange. The media retainer shall be designed to match the filter
elements to provide sufficient support for the multiple pleats of the filter element
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against the direction of the air flow. The media retainer shall be suitably coated and
designed to totally eliminate the possibility of oscillation and sagging.

The bag or packer shall inflate fully, shall not sag or flutter or be obstructed by
contact with other filter faces or ductwork surfaces when operation between 60 -
110% of design air volume flow rate for fixed volume system.

A complete set of all new filters shall be provided on every air handling unit at the
time of handing over.

c) FILTER PRESSURE DIFFERENTIAL MEASUREMENT AND INDICATION:

A differential pressure switch shall be provided for each filter bank.

3.4.1.11 Sand trap louver with filter

Fresh air louvers shall be of the sand trap type with vertical fixed blades
manufactured from anodized extruded aluminium. The bottom of any louver unit
when installed shall not be less than 1.0m above external ground level.
Louvered units shall be sized such that the face velocity does not exceed 1.75m/s.
The collection efficiency shall be between 72% and 86% based on sand to air ratio
densities between 1 and 22gms/m3 with a sand consistency of 92% between 150
and 425 microns. Size selection of sand trap louvers shall be strictly as per
manufacturer’s selection procedure.

3.4.1.12 Weather hood (for outdoor AHU)

Weather hood shall be of the same finish as the unit and must incorporate a
moisture eliminator of aluminium, consisting of corrugated mesh to eliminate water
penetration into unit. Hood to be factory installed. Outdoor air openings shall be a
minimum of one meter above the roof to prevent intake of dust and debris.

3.4.1.13 Heat Exchangers & Energy Recovery System

Heat recovery system such as heat recovery wheels, Cross flow plate type, heat
pipes and run around loops, can reduce the energy required to cool the fresh air by
harnessing the thermal energy of the facility’s exhaust air

3.4.1.13.1 Heat Recovery Wheels

(A) General

This section covers heat exchangers and installation of energy recovery wheels.
Whenever is required.
Quality Control: ASHRAE 84-78, Method of Testing Air-to-Air Heat Exchangers. ARI
Standard 1060-80. BS 5141 Part 1
Materials selection data to be submitted, Independent lab test report certifying
the cross contamination limit for recovery wheels.
a) Rotor / Wheels Matrix
The rotor/wheel matrix should be capable of both sensible and latent heat recovery
in the range of 80%. The ratio of weight of desiccant coating and the mass of
aluminium foil shall ensure equal recovery of both sensible and latent heat over the
operating range.

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b) Substrate
The substrate or wheel matrix shall be of pure aluminium foil to enable quick and
efficient uptake of thermal energy. The substrate shall be of sufficient mass for
optimum heat transfer and maximum heat recovery at a relatively low rotational
speed of 15 to 25 rpm.
c) Desiccant
The desiccant shall be water molecular selective and non-migratory and be of
sufficient mass. The desiccant to be coated with a non-masking porous binder
adhesive on the aluminium substrate which will allow quick and easy uptake and
release of water vapour.
d) Rotor
The rotor shall be a non-clogging aluminium media, having a multitude of narrow
aluminium foil channels, thus ensuring a laminar flow and will allow particles up to
600 microns to pass through it.
The rotor construction shall be of alternate flat and corrugated aluminium foil of
uniform width. The rotor honeycomb matrix foil shall be wound and adhered in a
manner to make the rotor structurally rigid and strong and does not allow cracking or
deformation due to temperature or humidity. The surface of the wheel/rotor shall be
highly polished so that the vertical and radial run out does not exceed 1mm per
1000mm which will minimise leakage/drag on the radial seals as well as fluctuations
in the drive belt tension.
The spacing of the substrate around the rotor should be extremely consistent so that
uniform air flow and performance over the entire face of the air stream is ensured. In
order to achieve uniform pressure drop and air flow across the rotor face the flute
height and pitch should be consistent.
The media should be cleanable with compressed air, low pressure steam or water
with light detergent; without degrading the latent recovery.
e) Purge Section

Built-in purge section should be provided in the unit to ensure maximum, separation
of fresh air from exhaust air to limit carryover of bacteria, dust and pollutants from
exhaust air to fresh air.
f) Seal
The wheel cassette shall be supplied with four pass labyrinth seal. The seals shall
not make any contact with the rotating surface of the wheel. Seals shall be field
adjustable to ensure optimum performance. The seal and purge system shall limit
cross contamination to less than 0.04%.
g) To be installed by AHU manufacturer at AHU factory.

3.4.1.13.2 Cross Flow Plate Type Heat Exchangers

The plate heat exchanger shall be designed for optimum heat transfers between the
supply and extract air streams. The heat recovery equipment shall be sealed to
ensure that there is no cross contamination between the supply and return air
streams.
Plate material shall be aluminium/stainless steel with condensate drains to remove
the condensate formed in the exhaust air section as the heat transfer takes place and
the relative humidity of the air increases.
It shall be equipped with a by-pass damper and factory fitted on-off actuator to allow
free-cooling and free-heating by the control system / BMS.

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The minimum heat exchange efficiency of the selected heat recovery equipment shall
be 60% at design flow rates; the maximum pressure drop of the heat exchangers
shall not exceed the AHU schedules.

3.4.1.13.3 Air-to-Air Heat Pipe Heat Exchangers

Heat pipes shall be included within the FAHU/AHU and wrapped around the main
cooling coil.

The external fins shall be of aluminum with a minimum thickness of 0.15mm. Fins
shall be of the continuous plate type and louvered type.

Tubes shall be of refrigeration standard seamless copper C106 for heat exchanger
use. Tube diameter shall be 12mm with a grooved inner surface and minimum root
thickness of the tube shall be 0.35mm.

Casings shall be from galvanized sheet steel with a minimum thickness of 1.6mm.
The casing shall incorporate tube plates and top and bottom plates around both the
pre-cool and reheat heat pipe blocks.

The working fluid shall be refrigerant type classified as ASHRAE safety group A1.
The heat pipe circuits shall be factory charged and hermetically sealed with the
calculated weight of refrigerant.

There shall be a multitude of loops in the height of the heat pipe and each loop shall
be individually charged. Heat pipes with header assemblies containing a single circuit
are not suitable as a single leak will render the entire heat pipe inoperative.

Heat pipe performance shall be independently type tested and certified in line with
the requirements of British Standards BS 5141 pt1 / European Standards EN 305 &
306 / American Standards ARI 410 for testing and rating of heat exchangers. All
software used to predict the performance of heat pipes shall be based upon the
results of these independent tests.

The heat pipe should have a third party independent test report conducted by a
certified laboratory from U.S.A / Europe.

The heat pipe manufacturer shall have minimum 10 years experience in

manufacturing of heat pipes and must have heat pipes commissioned for a minimum
period of 5 years in the Middle East market.

The number of rows and fins spacing shall be selected at the commonest ambient
conditions to achieve the most optimum performance of heat pipe throughout the
year.

3.4.2 Variable Air Volume (VAV) Units

3.4.2.1 General
VAV control units shall be installed in association with a variable air volume system,
having control of the fan output relative to system demands or Variable air volume
units shall be pressure independent bypass type.

Pressure stabilisers and air flow rate controllers shall be incorporated. Units shall be
factory-set or resettable as indicated and it shall be constructed from 20 gauge zinc
coated galvanized sheet steel, double wall with casing leakage rate to Class II, VDI
3803/DIN 24 194.
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The VAV units shall have multi leaf opposed blade dampers with neoprene seal and
external linkage, flanged connections on both ends complete with controller.
The digital thermostat shall be furnished by the terminal unit manufacturer and
include temperature set point and velocity adjustments located in the thermostat.
Controls must be factory fitted, wired and set according to design requirements.
The VAV units shall be selected for noise level NC24 for both discharge and
radiated. Integral sound attenuator shall be provided where required to limit noise
level. Unit shall be complete with electric heater section where specified.

3.4.2.2 Electronic Modulating Control

Units shall be provided with a modulating control package. The 24 volt reversible
actuator shall be factory mounted direct to the damper shaft and shall include
adjustable end stops as a standard feature.
The 24 volt modulating electronic thermostat for field mounting shall be supplied with
a (ºC) temperature scale. The thermostat shall be suitable for (vertical) (horizontal)
wall mounting. The thermostat shall be microprocessor based and provide
proportional plus integral control of air flow.

3.4.3 Constant Air Volume (CAV) Units

The CAV unit shall be pressure independent type, having low pressure loss, low
sound level to provide constant air flow with a percentage deviation not exceeding
2.5%.
Unit shall be galvanised steel sheet construction with casing leakage rate to class II
in according with the DIN 24194. Damper blades shall be of aluminium with
neoprene seals, aerofoil profile to control air flow. Damper spindle shall be supported
on self-lubricating nylon bearings.
The CAV unit shall be equipped with a factory installed “Flo-cross” type averaging
and signal amplifying air flow sensor to maintain constant airflow even with irregular
duct approach.
Units shall be complete with factory installed controllers. Units shall be pre-set at
factory for the scheduled airflow. It shall also be possible to carry out field resetting
of airflow when necessary. Units shall be selected so as not to exceed specified
noise levels for the respective zone.
Unit shall be complete with electric heater section where specified.

3.4.4 Fan Coil Units

3.4.4.1 General
a) The fan coil unit shall be Double-skinned.
b) All fan coil units capacity and air flow rate shall be selected based on the
performance of the units at medium fan speed.

c) In selecting the fan coil units, allowance shall be made for the actual
resistance imposed on the air flow of the units. The added resistance is to be applied
to all fan coil units whether shown to have ducts connected or not, and shall be
taken as not less than 50 Pa external to the unit.

d) Refer to Electrical specification for the following work: Power supply wiring
from power source to power connection on unit. Including starters, disconnects, and
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required electrical devices, except where specified as furnished, or factory installed

by manufacturer.

e) Manufacturer’s Qualifications: Firms regularly engaged in manufacture of

fan coil units with characteristics, sizes and capacities required, whose products
have been in satisfactory use in similar service for not less than 5 years.
Manufacturers shall have ISO 9001 certification.

f) Codes and Standard:

ARI Compliance: Test and rate fan coil units in accordance with ARI 441 “Standard
for fan coil units”; display certification symbol on units of certified models.
ASHRAE Compliance: Construct and install cooling coils in accordance with
ASHRAE 15 “Safety Code for Mechanical Refrigeration” and ASHRAE 33-for testing
air coils.
Insulation and adhesive shall meet NFPA-90A requirements for flame spread and
smoke generation. All equipment wiring shall comply with NEC requirements.
Unit capacity ratings shall be certified in compliance with industry Standard 441-66
for equipment, testing, and rating of fan coil air conditioners as administered at A.R.I.
Entire unit shall be Underwriter’s Laboratory listed and comply with National Electric
code. When units do not have A.R.I certified ratings, the contractor must perform
capacity tests of the completed installation, which are witnessed by the
Company/Consultant to confirm specified capacity is achieved while not exceeding
specified sound power levels.
g) Product Data: Submit manufacturer’s technical product data for fan coil units
showing dimensions, weights, capacities, ratings fan performance with operating
point clearly indicated, motor electrical characteristics, gages and finishes of
materials, and installation instruction.

Shop Drawings: Submit assembly-type shop drawings showing unit dimensions,

weight loadings, required clearances, construction details, and field connection
details.
h) Wiring Diagrams: Submit manufacturer’s electrical requirements for power supply
wiring to fan coil units. Submit manufacturer’s ladder-type wiring diagrams for
interlock and control wiring. Clearly differentiate between portions of wiring that are
factory – installed and portions to be field- installed.
i) Maintenance Data: Submit maintenance instructions, including instructions for
lubrication, filter replacement, motor and drive replacement, and spare parts lists.
Include this data, product data, shop drawings, and wiring diagrams in maintenance
manuals.
J) Deliver fan coil units with factory installed shipping skids and lifting lugs, pack
components in factory fabricated protective containers.
k) Handle fan coil units carefully to avoid damage to components, enclosures, and
finish. Do not install damaged components; replace and return damaged
components to air handling unit manufacturer.
l) Store fan coil units in clean dry place and protect from weather and construction
traffic.
m) Comply with manufacturer’s rigging and installation instructions for unloading fan
coil units, and moving them to final location.

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3.4.4.2 Materials
Units shall be complete with chilled water coil(s), electric heating coil (where
indicated on schedules), fan(s), motor(s), drain pan, and all required wiring, piping,
controls and special features.

3.4.4.2.1 Unit Chassis

Horizontal/Vertical Base Unit with Plenum for concealed installation shall have a
factory installed, galvanized steel plenum section sheet metal thickness not less than
1.6 mm and throw away/washable filter. Filters shall be washable type with minimum
15mm thickness and shall have at least 60% efficiency as per BS 6540: part 1: 1985
No. 3 test dust.
The plenum shall be either bottom or rear return, lined with 25mm thick glass fibre
insulation or equivalent based on manufacturer standard and include a removable
panel to provide an access to the fan/motor assembly. The access shall be
hinged/removable type and size should be bigger than the unit with locking
arrangements.
Horizontal cabinet unit for exposed installation shall be constructed of steel with re-
coatable baked enamel finish. Colour to be approved by the Company. Cabinet shall
be lined with 25mm thick glass fibre insulation or equivalent based on manufacturer’s
standard and have removable bottom access panel. Unit shall include hinged bar type
return air grille on rear of unit with throwaway/washable filter and integral double
deflection supply grille.
The motor and fan shall be mounted on a detachable mounting chassis that can be
removed from the fan coil enclosure as one assembly (with extended cables) to
facilitate fan and motor cleaning. It shall then also be possible to remove the fan
impeller scroll casing in order to properly clean the fan blades. Fan and motor
assemblies shall be complete with neoprene rubber anti-vibration mountings.

3.4.4.2.2 Fan /Motor

Fans shall be direct driven; double inlet double width fan wheels shall have forward
curved blades, centrifugal type and be statically and dynamically balanced.
Fan motors shall be 3 speed permanent split capacitor types with sleeve type bearings
and over sized oil reservoirs. Motor shall be suitable for 240V single phase, 50Hz
provided with internal thermal protection.

3.4.4.2.3 Coil
Coil shall be equipped with a 3 row coil (minimum) for installation in a 2 pipe system.
Coils shall have 12mm copper tubes, aluminium fins bonded to the tubes by
mechanical expansion and have a working pressure of 16 bars. Each coil shall have a
manual air vent and drain valve connection. All coils shall be leak tested and proven
tight. Alternate copper tube diameters shall be acceptable depending upon
manufacturing standards of the manufacturer and subject to approval by Company.
Each coil shall be provided with motorized 2-way/3-way control valve and isolation
valves. Flexible pipe connectors complete with union joints to facilitate removal of the
entire unit shall be provided. The connector shall be stainless steel braided polymer
tubing limited to 300 mm long and suitable for the system pressure.

3.4.4.2.4 Drain Pans

The drain pan shall be constructed of galvanized steel extending the entire length and
width of the coil(s) and pitched for drainage. The inside surface of the drain pan shall
be coated with closed cell fire retardant foam insulation. Outer surface of the drip pan
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to insulated to avoid the condensation. An extension drain pan shall be provided for
installation at the jobsite under the valve package.

3.4.4.2.5 Electric Heaters

Where indicated on schedules unit shall be equipped with electric resistance strip
heaters duct mounted.
Heaters shall include automatic reset high limit cut-out, contactor, factory furnished
junction box and fuse to protect the motor.
Heaters shall be single stage single phase, for 50Hz applications. Capacity shall be as
per the equipment schedule.
Control circuit for single power source connection shall be provided for motors and
heaters.

3.4.4.2.6 Controls
Each or multiple fan coil units shall be controlled by the room thermostat. Where
multiple fan coil units are controlled by a single room thermostat, a DDC based
controller with PID control action to be provided. The DDC controller shall send the
signal to the valve based on the room temperature and room thermostat setting. The
room thermostat shall have on/off switch, temperature sensor, set point adjustment
and fan speed (minimum two speeds) selector switch.
Room thermostat controlling single FCU shall be same as the room thermostat
controlling multiple FCUs but without DDC controller.
Manual on/off switches shall be fitted on all units irrespective of the automatic controls

3.5 Central Direct Expansion Units (Condensing Unit)

3.5.1 General
Central DX air-conditioning units shall comprise an outdoor air-cooled condensing
unit and matching indoor air handling unit with interconnecting refrigerant pipe work.
Both units shall be of the same manufacture unless specifically approved otherwise
by the Company.
The air condensing units shall be suitable for outdoor installation on the ground or
roof top. Units shall be completely factory-assembled and tested, piped, internally
wired and fully charged with CFC/HCFC free refrigerant.
Units shall be capable of operating at 25% of full load, or less, including hot gas
bypass as appropriate, and at occasional ambient temperatures in excess of 52oC.
Units shall be provided with compressors, condenser coils, fans, factory wiring,
piping and controls contained within the unit enclosure. Entire unit shall be provided
with spring isolator.
The unit shall be installed so that air can circulate through the condenser coils
without any hindrance, and the air discharged from the condenser fans is not
recycled. If the unit has to be placed near a wall or an obstacle that may prevent
satisfactory air circulation, sufficient distance as recommended by the manufacturer
shall be maintained between the unit and the obstacle.
A separate local disconnect switch near each unit shall be provided.

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3.5.2 Materials

3.5.2.1 Unit Cabinet:

The unit cabinet shall be constructed of with 14-gauge hot dip galvanised frame and
panel with 16 gauge zinc coated galvanized steel sheet, phosphatised and –painted
baked enamel finish. The finish passes 672 hours in salt spray application in
accordance with standard ASTM B117.

Unit access panels hinged shall stainless for control box services access, lifting holes
shall be provided to facilitate rigging. All parts of the unit shall be adequately
treated/protected to with stand harsh and corrosive climatic condition.

3.5.2.2 Fans:
Condenser fans shall be direct-driven propeller type, heavy gauge aluminium blades,
discharging air vertically up words. Condenser Fan motors shall be totally enclosed air
over (TEAO) with class F insulation, IP 55 protection, permanently lubricated bearings
and inherent corrosion resistance shaft. The motors shall be factory wired using
special silicon wires specially selected for high ambient operation with thermal load
protection.

The condenser fans shall be individually statically and dynamically balanced.

Complete fan assembly shall be provided with acrylic coated fan guard made from
heavy gauge galvanised wire.

3.5.2.3 Condenser Coil(s)

The condenser shall be air cooled, circuited for integral sub cooler, constructed with
seamless copper tubes mechanically bonded to aluminium fins /copper fins electro
tinned or micro channel condenser aluminium tube with aluminium fins with efficient
heat exchange arrangement.
Coils shall be factory leak tested at 450 psig air pressure under water. The aluminium
fins shall be ACRA-CLAD coating for effective corrosion treatment. The vendor shall
provide 5 year warranty for this coating. Coil wire mesh guard shall be provided to
avoid damage due to the elements and vandalism.

3.5.2.4 Compressors:
The condensing unit shall be with 2 or more independent circuits with semi-hermetic or
hermetic type compressors. Compressors shall be equipped with an automatically
reversible oil pump, operating oil charge, oil sight glass, suction and discharge shutoff
valve, crank case heater, refrigerant gas cooled motor, pre-set internal relief valve,
inherent thermistor motor protection. Compressor shall be mounted on spring isolators
with an isolation efficiency of no less than 95%.
The vendor shall guarantee the compressor for 5 years against failure.

3.5.2.5 Refrigerant Circuit:

a) Provide each unit with minimum two refrigerant circuits, factory supplied and
piped.

b) Minimum for each refrigerant circuit, provide:

i. Filter dryer.

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ii. Thermal Expansion device.

iii. Solenoid valve

iv. Suction and liquid line service valves and gage ports.

v. Charging valve.

vi. Compressor discharge service valve.

vii. Condenser pressure relief device.

viii. Moisture and liquid indicator.

3.5.2.6 Control and Safeties:

a) Minimum control functions shall include (1) Power and control terminal
blocks, (2) time delay protection to prevent compressor short-cycling. (3)
Lockout on auto-reset safety until from thermostat. (4) Capacity control on
the lead compressor shall be by suction cut-off un-loaders in response to
compressor suction pressure (5) Head pressure control by fan cycling.

b) Minimum safety devices shall include as Low oil pressure cut out switch,
LCD screen with minimum characteristics of 30, High discharge-pressure
switch, compressor over temperature cut out, low suction pressure switch,
and Condenser fan motors to be protected against overload, Phase loss, low
voltage and voltage spike protection.

c) The control of the unit shall be designed to communicate with HVAC control
panel using open protocol.

3.5.2.7 Execution
a) Maintain minimum manufacturer's recommended clearances for service and
maintenance.

b) Contractor shall provide and install all auxiliary devices and accessories for fully
operational condensing unit.

c) Install the units on a minimum 200mm height concrete base.

d) Provide connection to refrigeration piping system.

e) Vibration Isolation: Mount condensing units on restrained spring isolators with a

minimum deflection of 1 inch. Anchor units to supports.

f) Inter lock tiles/blocks shall be provided all around the units.

3.6 Unitary Air Conditioning Unit

3.6.1 Window Air Conditioners

Self-contained, through the wall, air-cooled air-conditioning units shall be provided
with diaphragm plate, mounting brackets and isolating switch. Units shall be installed
with piped condensate drains. Window AC unit shall be elegantly designed to suit
the interior decor and shall be complete with a hermetic sealed compressor, coils of
copper tubes and aluminium fins, evaporator fan with three speed control, Automatic
air sweep and cleanable filter.
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The Compressor shall be energy efficient fully hermitically sealed type 230 V + / - 10
%, single phase, 50Hz. The compressor Motor shall be suitably protected against
overloading using a removable suitably sized over load protection. These shall be
mounted on resilient mountings for quite operation.

Unit shall be super quit in operation, and shall have an energy efficiency ratio not
less than 4.4.

3.6.2 Mini Split Units

3.6.2.1 General
The split system shall consist of a indoor unit (evaporator unit) an outdoor unit
(condensing unit) and a wall mounted or wireless remote control switch, all factory
assembled and fully charged with refrigerant with zero depletion ozone refrigerant. All
units shall be start tested and checked at the factory. Units shall be designed for
continuous operation at outdoor ambient temperature of 52 deg. C. The distance
between indoor and outdoor unit shall not exceed 15 meters. Expansion device shall
of capillary tube. The refrigerant piping shall be K type copper complying with ASTN
B88 standard. The refrigerant used shall be environment friendly CFC/HCFC free.

3.6.2.2 Evaporator Unit

Evaporator units shall be of the type as scheduled.
a) Ceiling suspended and Wall mounted

Units shall be of the slim design with a decorative cabinet suitable for flush to ceiling
installation. Units shall include auto swing louvers for uniform air distribution. Unit
components shall be fully accessible for maintenance through the bottom panel.
b) Floor mounted and free standing

Floor mounting unit cabinet shall be enamelled steel with removable panels on front
and ends in colour selected by the company.
c) Ducted fan coil unit:

Generally, the ducted fan coil units shall comply with Sub-section of FCU unit
Specification with Direct expansion coils and controls. Indoor unit shall match with
the condensing unit.

Evaporator coils shall be of 9.5mm OD and 0.35 mm thick seamless copper tubing
mechanically bonded to 0.12 mm thick aluminium fins and shall be factory leak tested
at a pressure of 28 Kg/cm2. Cooling coil performance shall be rated in accordance
with ARI 410. A drain pan made out of galvanized sheet steel shall extend
throughout the length of the unit. The drain pan shall be coated with epoxy resin
enamel and insulated with 10mm thick polyurethane foam. The drain pan shall be
provided with a male drain connection on the service side.
Evaporator fans shall be three speeds direct driven, forward curved, centrifugal type
made of galvanized steel to deliver an accurate air flow at a low noise level. Fan
driving components shall be mounted on rubber pad isolators to reduce noise and
vibration.
Air filters shall unless otherwise specified be of the washable panel type and of
average weight arrestance efficiency not less than 85% according to ASHARE 52-
76.

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3.6.2.3 Condensing Unit

Casing of the unit shall be of 0.8 mm thick steel finished with ivory white acrylic resin
with removable access panel. Steel sheet metal shall be zinc-coated and galvanized
using the hot dip process. The condensing units shall be suitable for outdoor
application in an ambient of 52 °C; the equipment shall continue to function
satisfactorily without tripping of overheating at as maximum outside temperature of 55
°C.
The condensing unit shall have capacity as required scheduled. The condenser coil
shall be of non ferrous construction with aluminium plate fins mechanically bonded to
seamless copper tubing. The coil shall be coated for protection against saline
environment. Coil shall conform to ARI 410.
The unit shall be furnished with direct driven propeller type fan arranged for vertical or
horizontal discharge. The unit shall have a fan guard build of plastic/ steel wire and
offers quick access and easy maintenance. The condenser fan motor shall have
inherent protection and shall be of the permanently lubricated type.
The compressor shall be of the fully hermetic type and shall come equipped with
spring isolators and crankcase heater.
The controls shall be factory wired and located in a separate enclosure. Safety
devices shall consist of high and low pressure switches, motor temperature switch,
time delay relay, compressor overload devices and other protection devices as
recommended by the manufacturer.
Unit wiring shall incorporate a positive acting timer to prevent short cycling of
compressor if power is interrupted. All inter connecting wiring and piping between the
condensing unit and room units shall be by the contractor.
The contractor shall guarantee compressors for a period of 5 years from the date of
issue of practical completion certificate.
Casing shall make unit fully weather proofed for outdoor installation. The panels shall
be manufactured from heavy gauge galvanised steel, phosphatised and finished in
baked enamel powder paint.

3.6.2.4 Control
A control package shall be supplied with the unit with remote thermostat/fan speed/on-
off control facilities, which will control both units from within the conditioned space.
Control shall be microprocessor type with on-off timer, room temperature indicator,
energy saver facility, with multiple fan speed and other features.
The split units shall be interfaced with the BMS system for monitoring the run status of
the units, Also to be interfaced with fire alarm for shut down of the unit in the event of
fire.

3.6.3 Cassette Type Fan Coil Unit

Generally, the cassette fan coil units shall comply with Sub-section of Split unit
Specification.
The fan coil unit shall be of integrated cassette type which combines the supply air
slot, return air grille, fan, casing, cooling coil, heating coil (if required) into a single unit.
No connection of ductwork is allowed except for fresh air.
Fan coil units shall be selected at design duty and specified noise level with fan
running at medium speed.

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Each fan coil unit shall be provided with a combined room temperature sensor
complete with 3-speed controller and heating/cooling mode selector as specified.
Remote control unit shall be provided as specified in split unit specification.
Air cooling coil shall be constructed with copper tubes and shall be arranged
horizontally. Tubes shall have brazed copper return bends. Fins shall have smooth
drawn collars of length equal to fin spacing and mechanically bonded to tubes. Fins
shall be of the plate type, corrugated to ensure maximum air contact. Working
pressure of coil shall be of a minimum of 1200kPa and to suit system pressure design.
Each fan coil unit shall be provided with a stainless steel drain pan situated beneath
the cooling coil and arranged so that all moisture will collect in and drain from the pan.
Drain pans shall be insulated externally with a minimum of 25 mm approved type
foamed plastic. Each drain pan shall be fitted with a drain pipe which shall be
connected via suitable runs (correctly laid to fall) to the drainage system. Drain pans
shall have copper male connectors for connection to the condensate drain. The
connector shall be positioned to ensure rapid discharge of moisture from the pan.
Built-in condensate pump shall be provided for the removal of condensate water. A
water sensing system with low, high and warning limits shall be provided which
actuates the running of condensate pump at high water limit and trigger the alarm
system at warning level. When water level reaches the warning limit, the sensing
system shall cut off the unit operation. An alarm signal shall be given locally. The
signal shall be connected to CCMS or remote indication system as specified.
Condensate pump shall be designed to run continuously. The power source for
condensate pump and the associated control system shall be independent from that of
the fan coil unit such that the pump can still be operated after the units have been
switched off.
The filter media shall be of the washable type and shall be enclosed in a one-piece
formed stainless steel frame with covers flush mitred and reinforced by a die-formed
inverse bead.
Fan shall be of the quiet running direct driven centrifugal type with aluminium blades
mounted to a solid steel shaft. Fan motors shall be of the ‘split capacitor’ type suitable
for single phase electrical supply. The motor shall be resiliently mounted to the fan tray
or scrolls. The motor/fan tray assembly itself shall also be resiliently mounted to the
casing structure.
Manually adjustable louvers for directional airflow shall be provided for supply air slot
in each fan coil unit. Options shall be given to choose from 2-way, 3-way or 4-way
supply air discharge.
3.6.4 Packaged Air Conditioning Units

3.6.4.1 General
The package air-conditioning unit shall be factory assembled, single piece compact
unit comprising compressors/ air cooled condenser and evaporator, all assembled
on common base and encased in a weather proofed cabinet. The refrigerant used
shall be environment friendly CFC/HCFC free.
The base shall have slots and rigging holes to facilitate lifting and shifting of the unit.
The unit shall have connection/adaptor for supply and return air ducts. The unit shall
have a corrosion resistant sloped drain pan. The unit rating shall be in accordance
with ARI standards 210,270 & 360. All insulation and adhesives uses shall meet
NFPA 90A requirements for flame spread and smoke generation.

3.6.4.2 Casing
The Unit casing shall be constructed of 18G (minimum) galvanized steel, Zinc
phosphate coated, pre-coated with a baked enamel finish which shall be weather
proof. Internally insulated access panel shall be provided for ease of service and

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maintenance. The insulation used shall be 25mm thick, 24kg/m3 density fibre glass
acoustic insulation tightly fitted with a gasket on a rigid frame.
Cabinet panels shall be easily removable for servicing. Filters shall be accessible
through an access panel.
The manual damper shall permit up to 25% outdoor air for year round ventilation.
Holes shall be provided in the base rails for rigging shackles to facilitate overhead
rigging. Unit shall have a factory installed internal condensate drain connection and
a slopped condensate pan.

3.6.4.3 Fan
a) Evaporator Fan: The fan shall be centrifugal type belt driven with adjustable
motor pulleys. The fan wheel shall be made from steel, be of the double inlet type
with forward curved blades, and have a corrosion resistant finish. It shall be statically
and dynamically balanced and tested at the factory. Fan shaft shall be mounted on
two grease lubricated ball bearing designed for 200,000 hours average life. Fan
motor and fan assembly shall be mounted on common base to allow consistent belt
tension with no relative motion between fan and motor shaft. Entire assembly shall
be completely isolated from unit and fan board by double deflection, rubber shear
isolators.

b) Condenser Fan: The condenser fan shall be of the direct driven, propeller
type, with corrosion resistant blades riveted to corrosion resistant steel spiders. It
shall be dynamically balanced and discharge air vertically with protective grilles.
Motor shall be three phase with permanently lubricated ball bearing, built in current
and thermal over-load protection, and weather tight lingers over bearings.

3.6.4.4 Compressors
Hermetic or semi hermetic type compressor direct drive, 1750 RPM with isolated
mounting, integral suction accumulation, oil pump, oil filter screen, magnetic disc, oil
level sight glass, oil changing valve, lubrication for each bearing, connecting rod,
crankcase heater and well, double mesh suction inlet screen, high strength non -
flexing ring type suction and discharge valves, large gas passage and minimum
clearance volume, electric actuated unloading and replaceable un-loader solenoid
valves. Motor shall be suction gas cooled and shall have voltage utilization range
plus or minus 10 percent of nameplate voltages. Two winding thermostats imbedded
between three motor windings shall protect motor against excessive winding
temperatures. Safety controls shall include high and low pressure cut-outs, non
recycling pump down and rest relay. Compressor shall conform to ARI standard 520.
All controls and contactors shall be mouthed in weather-proof control box. The
compressor (s) shall have factory installed with vibration isolation. The factory
installed crankcase heater shall prevent refrigerant dilution of oil.

3.6.4.5 Coils
Evaporator Coil seamless copper tubing mechanically bonded to heavy duty
aluminium/copper fins of configurated design. All coils shall be factory pressure and
leak test at 2,070 kpa (300 psi). Coils shall conform to ARI 410. Casing and tube
shall be 18 gauge minimum galvanised steel.
Condenser coil configurated aluminium fin surface shall be mechanically bonded to
primary surface of seamless copper tubing. Sub cooling circuit (s) with liquid
accumulator shall be standard, Shall be factory tested at 3,100 kpa (450 psig) air
pressure, and vacuum dehydrated. Coils shall confirm to ARI 410. The coil shall be
coated with air dry “phenolic”, thermally set “here-site” or approved equal coating
suitable for salty sea cost with SO2 environment and shall be guaranteed.

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3.6.4.6 Refrigerant Circuit and Components

Refrigerant circuit components shall include, Filter driers and fixed expansion
devises, Service gauge connection on suction, discharge and liquid lines. Unit shall
have two independent refrigeration circuits.

3.6.4.7 Filter Section

Standard filter section shall consist of factory installed; 51mm (2-in) thick high
efficiency filters. Filter mount integral within unit and shall be accessible by hinged
access panels.

3.6.4.8 Controls and Safeties

The following safety devices trip and shut off the compressor, the unit shall
incorporate a solid state compressor protector which will provide reset capability at
the space thermostat:
1. Compressor over temperature, over current.
2. Low pressure switch.
3. High pressure switch
4. Freeze protection thermostat.

3.6.4.9 Motor
The compressor motors shall be of the refrigerant cooled type with internal thermal
overload protection and shall use calibrated circuit breaker for electrical protection.
All fan motors shall have permanently lubricated, sealed bearing and inherent
automatic reset thermal overload protection or manual reset calibrated circuit
breakers.

3.6.5 Variable Refrigerant Flow/Volume (VRF/VRV) System

3.6.5.1 General
Unit shall be air cooled, split type multi-system air conditioner consisting of one
outdoor unit and multi indoor units, each having capability to cool or heat
independently for the requirements of the rooms.
Up to ten different type and different capacity indoor units can be connected to one
refrigerant circuit and controlled individually. Maximum sixteen numbers of indoor units
shall be connected to a single refrigeration circuit.
Compressor shall be equipped with microprocessor controller, and capable of
changing the load based on response from Electronic thermostatic expansion valve
(EEV), EEV is fitted on to each of the indoor units based on load condition to follow
variations in cooling and heating load.
Outdoor units shall be suitable for match connection of all type of indoor unit.
The refrigerant used shall be environment friendly CFC/HCFC free.. The refrigerant
piping shall be extended up to 150m with 50m (*1) level difference without any oil
traps. Unit shall be equipped with and oil recovery system to ensure stable operation
with this long refrigerant piping.
Air conditioner shall operate continuously at the ambient temperature of 52°C. Both
indoor unit outdoor unit are assembled, tested, and charged with refrigerant at the
factory.

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*1: The value is based on the case where the outdoor unit is located above indoor unit.
Where the outdoor unit is located under the indoor unit, the level difference is a
maximum of 40m.

3.6.5.2 Outdoor Unit

The outdoor unit shall be a factory assembled unit housed in a sturdy weather proof
casing constructed from rust-proofed mild steel panels coated with a baked enamel
finish. Access panels shall be provided for easy service and maintenance and painted
steel wire guard for compressor section.

The connectable range of indoor units shall be from 0.8 to 10HP with all outdoor units.

The noise level shall not be more than 58 dB(A) at normal operation measured
horizontally 1m away and 1.5m above ground. The outdoor unit shall be modular in
design and should be allowed for side by side installation.

3.6.5.2.1 Compressor
The compressor shall be of highly efficient hermetic type and equipped with
microprocessor which capable of changing the load in accordance to the cooling or
heating load requirement.

The compressor motor shall be refrigerant gas cooled. Each compressor shall be
mounted on anti vibration mounts to minimize vibration transmission.
Compressor shall have discharge shut off valves, built in microprocessor controlled oil
separator, long life fine oil filter, insertion type oil heater with sleeve, oil sight glass, oil
fill and suction gas filter.
Each unit shall have two to three scroll compressors and be able to operate even in
case one of the compressors is out of order.
Compressor shall have inherent self analyzing lubrications system in which oil
pressure is maintained. The unit shall be provided with oil recovery system to ensure
stable operation with long refrigerant piping.

3.6.5.2.2 Heat Exchanger

The heat exchanger shall be constructed with seamless copper tubes mechanically
bonded to aluminium fins with efficient heat exchange arrangement.
Fins spacing shall be maximum 12FPI (2.1mm). The condenser fins shall be pre-
coated for saline and corrosive environment. Integral sub cooling circuit in each coil
shall be provided to increase the cooling capacity, without additional operating cost.
The coils shall be tested against leakage by air pressure of 450psig (3100kpa) under
water. The test certificates confirming the same shall be furnished.
The machine shall be finished with direct driven propeller fans discharging air upward.
Fans shall be constructed of corrosion resistant blades. All condenser fans shall be
individually statically and dynamically balanced for vibration free operation.

3.6.5.2.3 Refrigerant Circuit

The refrigerant circuit shall include an accumulator, liquid and gas shut off valves and
a solenoid vales. All necessary safety devices shall be provided to ensure the safety
operation of the system.

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3.6.5.2.4 Safety Devices

The following safety devices shall be part of the outdoor unit; high pressure switch,
fuse, fusible plug, over current protector for compressor, and short recycling guard
time.

3.6.5.2.5 Oil Recovery System

Unit shall be equipped with an oil recovery system to ensure stable operation with 150
running meter long refrigerant piping.

3.6.5.3 Indoor Unit

Each indoor unit shall be of the ceiling mounted cassette type, or ceiling mounted duct
type, or ceiling suspended type, or floor standing type, or concealed floor standing
type, or wall mounted type, or ceiling mounted cassette corner type.

It shall have electronic control valve which control refrigerant flow rate in respond to
load variations of the room.

The fan shall be of the dual suction multi blade type and statically and dynamically
balanced to ensure low noise and vibration free operation.

The address of the indoor unit shall be set automatically in case of individual and
group control.

In case of centralized control, it shall be set by liquid crystal remote controller.

3.6.5.4 Control
Computerized PID control shall be used to maintain a correct room temperature.

Unit shall be equipped with a self-diagnosis for easy and quick maintenance and
service.

The LCD (Liquid Crystal Display) remote controller shall memorize the latest
malfunction code for easy maintenance.

It shall be able to control up to 16 indoor units and change fan speed and angle of
swing flap individually in the group.

3.6.5.5 Central Remote Controller

A multi-functional centralized controller (central remote controller) shall be supplied for
common areas.

It shall be able to control all zones or all groups (each group consists of Max. 16 units)
of indoor units with the following functions.

a. Temperature setting for each zone, or group, or indoor unit.

b. On/Off as a zone or individual unit.
c. Indication of operating condition.
d. Select one of 10 operation modes for each zone.

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The controller shall have wide screen liquid crystal display and can be wired by a non-
polar 2-wire transmission cable to a distance of 1 km away from the indoor unit.

3.6.5.6 Unified On/Off Controller.

Unified ON/OFF controller up to 16 groups (each group consists of Max. 16 indoor
units) with the following functions.

a. On/Off as a zone or individual unit.

b. Indication of operation condition of each group.
c. Select one of 4 operation modes.

It shall be wired by a non-polar 2-wire transmission cable to a distance of 1 km away

indoor unit.

3.6.5.7 Schedule Timer

A schedule timer shall be supplied as:
It shall be able to set operation schedule of indoor units. The operation schedule shall
include twice on/off a day and holiday.

It shall be able to set 8 pattern of schedule combined with centralized controller.

3.7 Fans

3.7.1 General
Furnished and installed the fan as per required schedule. Fan selection and
installation depends upon a variety of factors including the application, space
availability, and noise considerations.

a) Quality Assurance: Manufacturer’s Qualifications: Firms regularly engaged in

manufactures of fans of types and sizes required, whose products have been in
satisfactory use in similar service for not less than 5 years.
Codes and Standard:
i) Fans shall be performance tested in accordance with BS 848.
ii) Motors shall comply with BS 5000.
iii) Impellers shall be dynamically balanced to ISO 1940 Grade 6.3.
iv) AMCA Compliance: Provide centrifugal fans bearing the AMCA Certified
ratings. Sound rate centrifugal fans in accordance with AMCA 300 “Test Code
for Sound rating air moving devices”.
v) ASHRAE Compliance: Test and rate fans in accordance with ASHRAE 51
(AMCA 210) “Laboratory Methods of Testing Fans for Rating”.
vi) UL Compliance: Provide fan electrical components which have been listed
and labelled by UL.
b) Submittals:
Product Data: Submit manufacturer’s technical product data for fans including
specifications, capacity ratings, fan performance, curves with operating point clearly
indicated, gauges and finishes of materials, sound power ratings with an octave
band analysis and installation instruction.

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Shop Drawings: Submit assembly-type shop drawings showing unit dimensions,

weight loadings, required clearances, construction details, and field connection
details.
Wiring Diagrams: Submit manufacturer’s electrical requirements for power supply
wiring to fans. Submit manufacturer’s ladder-type wiring diagrams for interlock and
control wiring. Clearly differentiate between portions of wiring that are factory –
installed and portions to be field- installed.
Pressure Calculations: Submit pressure drop calculations based on shop
drawings for approval by the Company before final selection of the unit.
Maintenance Data: Submit maintenance data parts list for each type of fan
accessory, and control. Include this data, product data, shop drawings, and
wiring diagrams in maintenance manual.
c) Product Delivery, Storage and Handling.
Deliver fan with factory installed shipping skids and lifting lugs, pack components in
factory fabricated protective containers.
Handle fan carefully to avoid damage to components, enclosures, and finish. Do not
install damaged components; replace and return damaged components to fan
manufacturer.
Store fans in clean dry place and protect from weather and construction traffic.
Comply with manufacturer’s rigging and installation instructions for unloading fans
and moving them to final location.

3.7.2 Products
General: For belt-driven fans, fan and motor shall have one-piece base with
adjustable motor mount. Each fan shall be provided with fan sheave, motor
sheave, matched V-belts and belt guard. Where motor is 10 hp (7.5 kW) or
less, motor sheave shall be variable pitch. Where motor exceeds 10 (7.5 kW)
hp. motor sheave shall be fixed pitch.
Fan motors shall be totally enclosed fan –cooled (TEFC), IP 56, with class F
insulation type.

Motor and fan shall be mounted on vibration isolators.

Roof fans for hazardous locations shall be backwardly inclined centrifugal, single
inlet, up-blast type. Fans shall be direct driven and motor shall be explosion proof.
The battery room extract fans shall be provided with terminal box and isolation
switch. The terminal box and the isolation switches shall be explosion proof type
suitable for zone one.

All Fan resistances shall be checked by the Contractor before any equipment is
ordered. Noise levels of fans shall comply with the room noise levels specified in
section-2 Appendix B.

Refer to Electrical specification for the following work:

Power supply wiring from power source to power connection on unit. Including
starters, disconnects, Interlock wiring between electrically operated equipment units
and between equipment and field installed control devices, required electrical
devices, except where specified as furnished, or factory installed by manufacturer.

Each fan assembly shall be supplied complete with lifting lug and earthlings boss.
An engraved nameplate shall be mechanically fixed to each fan. As a minimum,
the nameplate shall provide the following information:
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a) Manufacturers name and address

b) Date of manufacturers
c) Equipment Tag No.
d) Design air flow rate
e) Design air system resistance
f) Impeller speed
g) Direction of rotation
h) Direction of air flow
i) Electrical supply

3.7.2.1 Centrifugal Fans

a) Centrifugal fans shall be forward or backward curved, statically and
dynamically balanced and shall be designed and constructed in consideration of all
possible operating, start-up and shutdown conditions under all foreseeable ambient
conditions and as well as under a further increase of the fan speed by 10 %.

b) Fan casings shall be constructed of zinc coated steel sheet with angle
stiffeners and base angles to ensure freedom from drumming and shall be suitable
for operation at the maximum static pressure of the system. Fan casings shall be
constructed so that impellers can be easily withdrawn after installation. Outlets shall
be flanged and inlets shall be flanged or spigotted. A drain and plug shall be fitted to
the fan casing at its lowest point, an access door, for inspection and cleaning, shall
be fitted to the casing in an accessible position.

c) All centrifugal fans, handling more than 500 l/s (1000 CFM) shall have
backward curved blades unless shown otherwise. Impeller with backward/forward
curved blades for high efficiency shall be made of steel or aluminium, statically and
dynamically balanced on their shafts after assembly.

d) Impellers shall be of steel or aluminium; the blades shall be secured to the

hub or the blades and the hub shall be formed in one piece. The hub shall be keyed
to a substantial mild steel shaft or of smooth polished stainless steel and the whole
statically balanced. Blades shall have an aerofoil section. Shafts shall be carried in
two bearings which may be ball, roller or sleeve type. Lubrication nipples shall be
extended to the outside of the casing. An access door of adequate size shall be
provided. The fan shall be equipped with an inspection opening through which
electrical connecting and changing of blades position can be done without
difficulties.

e) Fan drive shall be V-belt type consisting of two endless anti-static type V-
belts capable of transmitting a power at least 75 % in excess of the rated brake
horse power (b.h.p.) of the motor and designed for trouble-free start-up and
operating conditions even if one of the belts is broken.

f) The fan motor shall be unit mounted, arranged on fan bases, designed for
extreme ambient conditions, maximum power consumption of the fan's characteristic
curve, three immediate starts one after another and 10 % power reserve at
minimum, including slide rails with clamping devices and adjustable belt tightness. A
belt guard consisting of an easily accessible and removable casing made of
reinforced and stiffened perforated steel sheets, spring or rubber vibration
mountings, a drain device and wire-mesh guards at the intake air cones of the fan
casing shall be provided.

g) The Complete casing shall be horizontally and vertically divided to be

capable of being dismantled if so required for transportation, installation or
maintenance purposes.

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3.7.2.2 Axial Flow Fans

a) Axial flow fans shall be designed and constructed in consideration of all
possible operating, start-up and shut-down conditions under all foreseeable ambient
conditions.

b) The cylindrical casing shall be made of galvanized or painted heavy gauge

steel sheet, reinforced and stiffened with connecting flanges. The length of the duct
casing shall be greater than the length of the fan(s) and motor(s), in such a manner
that the complete section may be removed without disturbing adjacent ductwork.

c) Casings shall be rigidly to obviate drumming and vibrations. Fabricated steel

shall be provided where necessary for bolting to the base or supports.

d) The fan shall be consisting of a impeller with profiled aero-foils blades for
high efficiency and designed of the variable pitch type, continuously adjustable at
stoppage and completely made of aluminium alloy, statically and dynamically
balanced, and combined with flexible and non-rotatable canvass connections, spring
or rubber vibration mountings, an electrical motor designed for maximum power
consumption of the fan's characteristic curve, including a separate water-tight and
dust proof terminal box fastened to the outside of the fan casing and connected with
the motor terminal box by a cable with outside protection tube and combined with a
wire mesh, if so required.

e) Inlet and outlet ducts shall terminate in flanged rings for easy removal. Fans
shall be selected to operate at not more than 80% of maximum capacity.

3.7.2.3 Propeller Fans

a) Propeller fans shall be either ring mounted or sleeve mounted type. Where
they are mounted in sleeve, the casing shall be longer than the length of the motor
and impeller. The casing shall be of galvanised steel, with flanged ends and
incorporate an inspection door. A terminal box shall be mounted externally on the
casing. The maximum speed of fans shall be limited considering noise.

b) Impeller shall be of aluminium, the blades shall be fastened to the hub of the
blades and the hub shall be formed in one piece. The bearings may be of ball, roller
or sleeve type.

c) Back-draft dampers shall be provided on the discharge side of each

propeller fan. Fan, motor, wall housing and accessories shall be suitable for outdoor
installation.

3.7.2.4 Wall/Window Mounted Extract Fans

a) Extract fans shall be of the propeller type suitable for wall/ window mounting.
b) Front cover shall incorporate a finger guard for improved safety. Removal of
front cover shall stop the fan motor and isolate accessible wiring.
c) Motor shall be lubricated for life and shall be fitted with a thermal cut out
providing protection against accidental overloading.
d) Fans shall include air operated back draft dampers.

3.7.2.5 Ducted Inline Extract Fans

a) Housing shall be of pressed galvanized steel. Impellers shall be backward
curved centrifugal design driven by speed controllable motors with integral thermal
protection. Motors shall be squirrel cage induction type suitable for 240V/1PH/50Hz
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or 415V/1PH/ 50 HZ electric supply. Bearings shall be ball type, sealed for life.
Speed controllers shall be supplied by fan manufacturer.

b) All extract fans shall have louver and back draft damper at the end of the discharge
duct except small glass mounted fans which shall have built in exhaust side shutters.

3.7.2.6 Twin Fans

a) Unit casing shall be manufactured in epoxy coated aluminium alloy and shall
house twin fan assemblies, each comprising forward curved centrifugal impellers
running in an individual scroll. Impellers may be either direct driven or belt driven
depending upon the fan duty. Motors shall be TEFC type with sealed for life bearings.
Motor insulation shall be Class 'F'.
b) Fans shall be fitted with air flow sensors and shall discharge into a common
plenum chamber through a linked shutter system. Motors and flow sensors shall be
prewired to fitted isolator accessible from outside.
c) Units shall be supplied for either roof mounting or plant room use as required.
Units shall be supplied with auto changeover panels with duty/standby selector switch,
run/fail indication lamps, cyclic relay for duty sharing. Starter/Auto changeover panels
shall be incorporated within electrical power supply panels.

3.7.2.7 Roof Extract Units

a) The exhaust fans mounted on the roof shall be of centrifugal, vertical /
horizontal discharge type. The impeller shall be backward curved centrifugal type,
statically and dynamically balanced and made of aluminium.
b) The housing shall be manufactured from corrosion resistant stable spun or
pressed aluminium sheet metal. Bird screen, base plate and motor casing made of
aluminium shall be provided.
c) A self-activating aluminium back draft damper/shutters shall be provided. This
damper shall open automatically when the fan starts and close automatically when the
fan shuts off by stainless steel spring.
d) The material shall be strong, light in weight, shall give excellent resistance to
atmospheric corrosion and shall be suitable for operational use in a wide range of
climatic conditions.
e) The unit shall be load tested to ensure a generous structural factor of safety
enabling the units to withstand all normally encountered weather conditions. The
cowl shall be secured to the mounting brackets by stainless steel screws.
f) Fan support arms shall be of mild steel, reliantly mounted to the base.
g) Motors shall be metric sized, ball bearing, squirrel cage induction type, for
direct on line starting. All motors shall have Class F insulation with degree of
protection IP55.
h) Motor bearings shall be pre-lubricated with high quality grease at ambient
temperature up to 70 deg. C.
i) All fixings shall be none rusting and units shall be fitted with discharge guard.
j) Each unit shall be finished in polyester powder paint to a colour to be agreed
with the company engineer.
k) Electrical isolators shall be fitted as standard and shall be located behind a
quick release cover and shall be externally accessible without the need to remove
access panels. Isolators shall be suitable for the motor to which they are connected.

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3.7.2.8 Explosion Proof Exhaust Fan Ducted Type.

a) Exhaust fans shall be direct driven or belt driven fans with none overloading,
backwardly/forwardly inclined wheels. Fans shall be single inlet, single width, with
clockwise rotation. Air discharge position shall be top unless specified otherwise.
b) Fan housing shall be of heavy gauge stainless steel/special epoxy coated
Aluminium alloy suitable for battery room operation with maximum corrosion
protection.
c) The impeller shall be spark proof statically and dynamically balanced and shall
be made of corrosion-resistant aluminium, designed and constructed to provide
maximum performance and efficiency.
d) Fans shall be explosion proof suitable for zone 1, T4 rating, Gas Group IIB/IIC,
high efficiency, totally enclosed with Class 'F' insulation. Fans shall be UL certified.
Motor shall be out of the air stream.
e) All the components of the fan in contact with air shall be provided with factory
applied baked here-site/epoxy coating.
f) Fans shall be licensed to bear the AMCA Air and Sound Certified Ratings
Seal. Fan air performance ratings shall be bear on test conducted in an AMCA
registered laboratory for AMCA 210 air performance testing. The test standard used
shall be ANSI/AMCA Standard 210-85, ANSI/ASHRAE Standard 51-1985 "Laboratory
Methods of Testing Fans for Rating", AMCA 99-0401 type B “ spark resistance fan
construction”.
g) Extract system for battery room shall be independent of other extract systems.
Battery extract fans shall be provided on an N+1(working +stand by) basis with auto
change over on duty fan fail and duty sharing.

3.7.2.9 Explosion Proof Exhaust Fan Wall Mounted Type

a) Fans shall be explosion proof suitable for zone 1, T4 rating, Gas Group IIB/IIC,
high efficiency, totally enclosed with Class 'F' insulation. Fans shall be UL certified.
b) Exhaust fan shall be manufactured in weather resistant polymeric material.
Integrated component designed for maximum aerodynamic efficiency.
c) The fan shall be suitable for operation in ambient temperature up to 55⁰C fitted
with thermal overload protection trip.
d) Shall be of integrated component design allows all parts to be dismantled for
cleaning without the use of specialist tools.
e) Exhaust fan shall be provided with its own control switch.
f) Shall have a wall louver and shall be provided with back draught damper.

3.8 Duct Work

3.8.1 General
The specialist ductwork company selected shall have sufficient expertise,
organisational ability, drawing office production capacity and site erection capability
to deal with a project within the proposed construction programme.

Ductwork dimensions are internal; make allowance for any internal lining. Ensure
that ductwork installation complies with the requirements for thermal and acoustic
insulation specification.

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All supports, stiffeners, flanges etc. used in ductwork construction and installation
shall be hot dip galvanized.

Ductwork shall be off site pre-fabricated according to the requirement as specified in

the Particular Specification. The ductwork shall be fabricated from good quality full
sized zinc coated hot dipped galvanised flat steel sheet to BS EN 10142, coating
type Z275 unless otherwise specified in the Particular Specification or the Drawings.
Supply duct shall not be passing over or crossing any panels.

3.8.1.1 Quality Assurance, Code and Standards

Ductwork shall comply with the latest edition of the HVCA publications DW/144 for
sheet metal ductwork (low-medium- and high pressure) with additions or
amendments as required or specified by this Specification and/or elsewhere in the
documents.

Where any part of the installation is not covered by the above, the recommendations
of the latest edition of “Ductwork Construction Standards" issued by the Sheet Metal
and Air Conditioning Contractors' National Association (SMACNA) Inc. USA shall be
applied.

ASHRAE Standards: Comply with ASHRAE Handbook, Equipment Volume, “Duct

Construction”, for fabrication and installation of metal ductwork.

Manufacturer’s Qualifications: Firms regularly engaged in manufacture of metal

ductwork/accessories (as applicable) of types, materials and sizes required whose
products have been in satisfactory use in similar service for not less than 5 years.
Installer’s Qualifications: Firm with at least 5 years of successful installation
experience of projects with metal ductwork systems similar to that required for
project.

3.8.1.2 Submittals
Product Data: Submit manufacturer’s technical product data and installation
instructions for ductwork materials and products.
Shop Drawings: Submit scaled layout drawings of metal duct work and fittings
including, but not limited to, duct sizes, locations, elevations and slopes of horizontal
runs, wall, roof and floor penetrations and connections. Show interface and spatial
relationship between ductwork and proximate equipment. Show modifications of
indicated requirements, made to conform to local shop practice and how those
modifications ensure that free area, materials and rigidity are not reduced.
Record Drawings: At project closeout, submit record drawings of installed metal
ductwork and ductwork products.
Maintenance Data: Submit maintenance data and parts lists for metal ductwork
materials and products. Include this data, product data, shop drawings and record
drawings in maintenance manual.
Provide mock up installation for approval by Company before progressing with work.

3.8.1.3 Delivery Storage and Handling

Protection: Protect shop- fabricated and factory-fabricated ductwork, accessories
and purchased products from damage during shipping, storage and handling.
Prevent damage and prevent dirt and moisture from entering ducts and fittings.
Storage: Where possible, store ductwork inside and protect from weather. Where
necessary to store outside, store above grade and enclose with waterproof wrapping.
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Store and handle sealant and fire stopping materials according to manufacturer’s
written recommendations.
3.8.2 Materials

3.8.2.1 Sheet Material

a) The ductwork shall be fabricated of galvanised steel sheet exception of specially
mentioned from good quality full sized zinc coated hot dipped galvanised flat steel
sheet to BS EN 10142, coating type Z275 or ASTM A653A, 653M, G90. The
galvanizing shall be carefully done and the sheets shall be of such quality that they
may be bent flat on themselves with no fracture to the coating or the base metal.
b) Stainless Steel. Stainless steel ductwork shall be made with ASTMA 480,
Type 316, sheet form, with No. 4 finish. Extract ductwork handling corrosive gases
(battery rooms and laboratory) shall be stainless steel 316 construction.
c) Kitchen and dishwasher extract ductwork shall conform to NFPA 96 and
shall be air and water tight welded construction manufactured from 18 gauge
Stainless steel sheets in accordance with BS 1449, Part 1 Grade CR4 GP.
Ductwork shall be painted on the outside with two coats of heat resistant galvanic
paint after manufacture. Provide access panels for cleaning of ducts. More details
are specified in specialist area section-1 kitchen in this specification.
d) Laundry extract ductwork shall be air and water tight construction
manufactured from aluminium sheets in accordance with BS 1470.
e) Reinforcement Shapes and Plates. Unless otherwise indicated, provide
galvanized steel angles for reinforcing where installed on galvanized sheet metal
ducts. For stainless steel ducts, provide reinforcing angles of compatible materials.
f) Tie-Rods. Galvanized steel, 8 mm minimum diameter for 900 mm length or
less; 10 mm minimum diameter for lengths longer than 900 mm.

g) Hardware. Nuts, bolts, screws, rivets, and other miscellaneous fasteners

used for duct systems shall be compatible with the ductwork material. For galvanized
steel, hardware shall be galvanized cadmium-plated, shall have other corrosion-
resistant finish, or shall be made of a corrosion-resistant material.

h) All supports, stiffeners, flanges etc. used in ductwork construction and

installation shall be hot dip galvanized otherwise specified.

i) The Specification DW/144 shall be used as a guide to the minimum standard

of construction. The ductwork specialist shall use thicker gauge material or company
alternative approved methods of strengthening the ductwork as considered
necessary and shall ensure that the ductwork is free from vibration and drumming.
The minimum nominal sheet thickness for any ductwork shall be 0.8 mm (22 gauge),
mounted internal to a building and 1.6 mm (16 gauge) externally.

3.8.2.2 Flexible Duct Work

Flexible ductwork shall be lightweight aluminium laminated duct suitable for low and
medium pressure systems. The aluminium laminated construction shall encapsulate
a high tensile steel wire helix between two layers of 0.9 micron thick aluminium plus
12 micron thick polyester. Flexible ducts shall be with factory applied thermal
insulation and vapour barrier.
Core shall be factory pre-insulated with a total thermal performance of R 3.5 or
greater. Outer jacket shall be a fire retardant polyethylene vapour barrier jacket with
a perm rating not greater than 0.10 per ASTM E 96, Procedure A.
Flexible ductwork shall be suitable for an operating temperature range of -5°C to
120°C.
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Duct must comply with the latest NFPA Bulletin 90A and be listed and labelled by
Underwriters Laboratories, Inc., as Class I Air Duct, Standard 181, and meet flame
spread less than 25; smoke developed less than 50.
Flexible duct shall be one-piece, 1000 mm maximum in length and shall not be
installed so that it lies on the ceiling.

3.8.2.3 Flexible Connections

Flexible ductwork connections shall be provided at connections to fan inlet and
discharge connections, all connections to air plant containing vibration generating
equipment and at all points where ducts cross structural expansion joints and for any
other locations where indicated on the drawings.
Flexibles shall be flame resistant UL listed; water proof, non-organic, flexible sheet
secured with flat galvanised steel bands, and fixed to give a smooth internal
ductwork surface.
Flexible connections shall have a minimum effective length of 50 mm and a
maximum effective length of 250 mm. Flexible connections shall be considered as
part of the ductwork system when considering leakage rates, or fire protection
integrity and stability.
In cases where excessive noise breakout through flexible connections may cause
the noise design criteria to be exceeded, a heavy duty acoustic material shall be
used to wrap the joint. The ductwork shall not impose any load on the flexible joint.

3.8.2.4 Pre-insulated Phenolic Duct Work

Where specified in the Particular Specification or the Drawings, pre-insulated
ductwork made from thick rigid closed cell phenolic foam in rigid board form may be
used. A phenolic duct work installation must meet the minimum requirements of an
equivalent conventional galvanised sheet metal ductwork system.
The ductwork material shall be covered with a layer of vapour barrier jacket on both
board facing. The vapour barrier aluminium foil and board thickness shall be of as
per manufactured recommended to suit the different environment. The thermal
conductivity of phenolic panel shall not be more than 0.025 w/m-K. The
circumferential and longitudinal seams of the vapour barrier foils shall be sealed with
self-adhesive foil tape.
All material shall have a class 'O' fire rating. Low smoke emission shall comply with
BS 5111 Part 1 and shall be CFC & HCFC free with zero ozone depletion potential.
The flange system for the phenolic foam ductwork shall be designed to eliminate the
effect of "Cold Bridge" and for the purpose of sealing; the flanges shall be coated
with fire resistant gaskets and securely mounted with sufficient bolts, nuts and clips.
An established joining system shall be employed in connecting the ductwork and
accessories such as air outlets and dampers. The joining system shall be approved
by the Company.
The construction and installation including all cutting tools, adhesives, flange system
shall be strictly in accordance with the recommendations of the phenolic foam
duckboard manufacturer's instruction.

3.8.2.5 Volume Control Damper (Balancing Dampers)

Dampers for air balancing shall be provided at supply, exhaust and return air main
branches, fresh air inlets, the inlet spigot to diffuser plenum boxes, adjacent to each
fan in the main duct and where required for proper air balancing. Dampers shall be
manually adjustable externally, with indicating quadrant and lockable operating lever.

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All dampers shall be complete units with flanged duct connections, independent
housings opposed double skin aerofoil section blades, low pressure drop and low
leakage type with seals on blade edges and casing jambs within a square casing
with in accordance with DW / 144 Section 21.2.2.and control mechanisms.
Dampers with side dimensions up to 300 mm shall have a single blade, not less than
1.6 mm thick, with 10 mm diameter pivot rods and rigid bearings.
Dampers with side dimensions over 300 mm shall have horizontally opposed multi
leaf blades, not less than 1.6 mm thick and blades no more than 250 mm wide, with
10 mm diameter pivot rods set in rigid bearings and linked externally to a single
operating lever and quadrant.
Frame and Blades shall be constructed from the same material of the ductwork or of
stainless steel encapsulating an internal double contoured steel longitudinal
reinforcing bar, mounted on steel spindles.
Bearings shall be of nylon material and the units shall be of low-leakage design by
incorporation of synthetic trailing edge seals and a peripheral gasket which shall be
tested according to BS 476 Part 6 and 7.
Unless otherwise specified, quadrants and operating handles shall be of die-cast
aluminium or other material approved by the company with the words 'OPEN' and
'SHUT' cast on the quadrant.
Each air volume control damper in the ductwork shall be fitted with a non-corrodible
label stating the actual air flow in (m3/s) when in the fully open position, its overall
cross sectional area and the design or actual air flow.
Access openings with readily removable or connected with safety wire air sealed
covers shall be provided adjacent to all dampers, unless access is available through
adjacent equipment. Subject to limitations of ductwork size the dimensions of access
openings shall not be less than 450 mm x 450 mm and they shall be located so as to
afford easy access for inspection and maintenance.
After final commissioning, the position of all dampers shall be secured and indicated
with a durable mark on the quadrant.

3.8.2.6 Fire Dampers

Fire dampers shall be provided in ductwork in the following locations:-
a) Wherever a ductwork passes through a floor slab, wall and roof.

b) Other locations as required by the Particular Specification and the Drawings.

Fire or Smoke dampers used singly or in combination shall have an overall fire rating
not less than that indicated and certainly not less than that for the wall or floor slab in
which they are situated Scope of supply of fire dampers should include necessary
sleeves and retaining angles for fixing.

Fire dampers made to British standard B.S. 476 or North American Standards or
N.F.P.A. 90A, with minimum 2-hours rated, UL listed and shall be labelled by
manufacturer. Each Fire damper casing shall be air tight, continuously welded and
clearly marked with a permanent indication of the direction of air flow. All Fire
dampers shall also be approved by the civil defence/Fire Services Department.

Remote position indication of fire damper to be considered in DDC or local HVAC

control panel.

Fire damper assemblies for installations in corrosive environments shall be

fabricated from suitable materials resistant to the corrosive substances. Alternatively,
the material may be coated with a protective finish to produce the same effect.
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3.8.2.6.1 Curtain Type:

Fire dampers shall be interlocking blade type sized and selected to provide a
nominal 100 percent free area (curtain completely clear of the airstream) in all sizes.
The design shall incorporate complete factory-assembled and sealed units with all
parts as required to provide a UL approved installation. Scope of supply of fire
dampers should include necessary sleeves and retaining angles for fixing.
Fire damper construction shall be of galvanized steel casing, galvanized steel blades,
and fitted with catch plates, stainless steel closure springs and stainless steel seals.
An automatic locking device shall be provided to ensure that the blades are held in the
closed position after release. Blades shall be out of the air stream. Fusible links shall
be rated for a fusing temperature of 72-74°C unless otherwise specified. Fusible
links on fire dampers shall be constructed in accordance with UL 33.

Access panels with airtight gasket shall be provided to fire dampers enabling full
inspection of blades and the fusible links.
A least 2 Nos. fusible link shall be supplied as spare.
Fire dampers handling outside air shall be fabricated from stainless steel. A fire
damper installation frame shall be provided.

3.8.2.6.2 Smoke Dampers

Smoke dampers shall be provided in ductwork in the following locations:-
 Same as fire damper (3.8.2.6)

Smoke dampers shall be the low leakage type, rated under UL 555 S as leakage
Class I.
Frame shall be of formed channel of not less than 1.6 mm (16 gauges) galvanised
steel. Blades shall be 2 mm (14 gauges), air foil shaped, double skin construction,
opposed blade type.
Damper actuators shall be factory furnished suitable for either 240 volt or 24 volt
application UL listed. Complete unit shall be factory tested in compliance with UL
555S and shall be UL label.
The damper shall at all times be connected to the actuator for controlled closure in not
less than 7 seconds and no more than 15 second.
The damper unit shall be supplied with a two position indicator switch linked directly to
the damper to provide the capability of remotely indicating damper blade position.

3.8.2.6.3 Combination Fire/Smoke Dampers:

Each combination fire smoke damper shall be 2 hour fire rated under UL Standard
555, and shall further be classified by underwriters laboratories as a leakage rated
damper for use in smoke control systems under the latest version of UL555S, and
bear a UL label attesting to same.
Combination fire smoke dampers meeting or exceeding the following specifications.
Frame shall be a minimum of 16 gage galvanized steel formed into a structural hat
channel shape with tabbed corners for reinforcement. The blade shall be aerofoil
1.6mm (16 gages) minimum galvanized with three longitudinal grooves for
reinforcement. Bearings shall be stainless steel sleeve turning in an extruded hole in
the frame.
The damper casing shall be of double-skin galvanized steel construction with
continuously welded corners and integral spigot connections. The dampers shall be
supplied complete with the manufacturer-installed frames.

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In addition to the leakage ratings already specified herein, the dampers and their
actuators shall be qualified under UL555S to an elevated temperature of 176°C
(350°F); appropriate electric actuators shall be installed by the damper
manufacturer at time of damper fabrication. Damper and actuator shall be supplied
as a single entity which meets all applicable UL555 and UL555S qualifications for
both dampers and actuators. Manufacturer shall provide factory assembled sleeve.
Damper and actuator assembly shall be factory cycled 10 times to assure operation.
Blade position indicator: Each combination fire smoke damper shall be equipped
with switch package which shall include two position indicator switches linked
directly to the damper blade to provide the capability of remotely indicating damper
blade position.
Fusible link: Each combination fire smoke damper shall be equipped with a fusible
link which shall melt at 72-74°C causing damper to close and lock in a closed
position.
Damper actuator selection shall be based on fail closed operation, in which the
damper closes when power is interrupted to the actuator. The damper shall be
released to the closed or fail-safe by an independent closure spring on loss of power
supply, either by genuine power failure or by the zone fire signal actuated by the
smoke detection system.
Each actuator for fire smoke damper shall be linked with HVAC control panel for
command input signal. The closing time for actuator shall not be more than 15
seconds.
The damper shall be automatically reset on resumption of power supply by built-in
motor of 220V AC or 24V AC/DC.
Provide Re-settable, re-usable link control device with high limit temperature sensor
that causes the damper to return to fire protection mode (closed) when temperatures
reach the operation limit of the damper/actuator assembly and meets all NFPA 92 A
requirements.

3.8.2.7 Access Panels

Duct access panels shall be minimum 450 x 450 mm. unless restricted by duct
dimensions. All access panels shall be constructed from galvanized steel sheets, 25
mm apart with necessary reinforcing inside for rigidity, with space filled with glass fibre
insulation. Panels shall be made airtight with a continuous neoprene rubber gasket.
Openings in ductwork shall be provided with continuous galvanized reinforcing bars,
which on insulated ductwork, shall be extended to the face of the insulation. 'Small'
panels shall be provided with at least two self tightening cam locks. All panels shall
have drawer type handle.
Apparatus access doors shall be minimum 600 x 1500 mm with angle or channel
frame. Provide two 75 mm strap hinges with brass pins; and two handles minimum,
operable from inside and outside. All access panels shall be hinged type constructed
from double thickness 18 gauge (1.3 mm) galvanized steel, with 25 mm insulation
between sides with necessary reinforcing for rigidity. Doors shall be made airtight with
"tadpole" gaskets.
Provide access panels where shown on drawing, required and directed and in the
following locations:
Bottom of all duct risers, Next to outside air intakes and outlets
At each fire damper. Into apparatus casings to facilitate maintenance and cleaning of
all component.

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3.8.2.8 Motorized Shut off Dampers.

Motorized shut-off dampers shall be open or close by motorized mechanism. The
Contractor shall furnish and install, control dampers as required for the proper
functioning of the system.
All control dampers shall be opposed blade.
Casing shall be in galvanized sheet steel to BS 2989 Z2 G275 M.
Blades shall be of natural anodized extruded aluminium to BS 1474.
Blade tip seals silicon rubber, temperature resistant up to 200 deg. C.
Side seals shall be stainless steel to BS 1449 Grade 302-525.
External blade linkage shall be stainless steel to BS 970 304-S 15.
Blade spindles shall be in stainless steel to BS 970 304 S11 supported in plain brass
bearings.
Shut off dampers shall have a leakage rate not exceeding 200 M3/hr/M2 at 1000Pa.
When mounting the actuator outdoor it has to be certain the actuator is protected
against direct sun exposure and rain. Actuator for hazardous area shall be explosion
proof type.

3.8.2.9 Back Draft Dampers.

Back draft dampers shall be low leakage with parallel blades and neoprene edge
seals.
Dampers frames shall be constructed from galvanized sheet steel with Aluminium
blades. Blade stub shafts shall be brass with PVC bearings. Sealing strips on blades
shall be polyester foam.

3.8.2.10 Pressure Relief Dampers

Pressure relief dampers shall be multi parallel blade with weighted arm closing assist.
The frame shall be anodized Aluminium channel sections with formed Aluminium
blades. Maximum blade length shall be 100 mm, and polyester foam seating strips
shall be incorporated on blade edges. Bearings shall be in PVC with non-corrodible
shafts.

3.8.2.11 Duct Mounted Electric Heater

Duct mounted electric heaters to meet temperature criteria. Each electric heater
shall be controlled with a thermostat and shall be equipped with an automatic and
manual reset thermal cut-out and air flow cut off switch, ON/OFF indication lamp.
Duct mounted heater shall be sized for the greater of either the winter heating load
or the peak reheat load during the cooling mode. A15 percent safety factor shall be
applied to the heating load.
Duct mounted electric heaters shall be finned tubular flanged type construction with
SCR control. Direction of air flow, voltage, size, wattage and airflow capacity shall be
as per designed scheduled. Heaters shall be UL listed for zero clearance and shall
meet all applicable NEMA requirements.
Elements shall be finned tubular type having Ni-Chrome resistance and stainless
steel plated sheath. Elements wire shall be 80/20 Ni chrome. Terminals shall be
sealed with silicone rubber to protect against moisture.
Electric heater frame and controlled box shall be fabricated from heavy gauge
aluminized steel. Frames shall have flanges with pre-drilled holes designed for
mounting between flanged sections of ductwork. Control box shall be hinged, solid
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cover type. Fiberglas insulation, 40mm thick and 16kg per cubic meter density or
greater, shall be used between the heating coil and control box for condensation
protection.
Terminal box shall be provided with solid cover to minimize dust infiltration and shall
be hinged interlocking disconnect switches shall be provided.
Heater terminal box shall be rated at 105 deg. C and 600V. Main supply terminals
shall be provided for copper supply wires. Built-in component shall include
disconnecting break magnetic three pole contractors, safety disconnect with door
interlock switch, control transformer with primary fusing, minimum two step
controller, pressure – type airflow switch, branch circuit fusing, “ power on” pilot light,
and single terminal block to accept the number, type and size of conductors as per
electrical specification.
Safety devices shall be a linear limit automatic reset terminal cut-out for primary over
temperature protection and a secondary linear limit cut-outs with manually reset in
the power lines to de-energize elements if the primary cut-out fails. All safety devices
shall be serviceable through terminal box without removing heater frame from duct.
Due to safety and operational reasons the duct heater shall not be used if the height
of the bottom of duct- where the heater will be installed-is more than 3.5 meter

3.8.2.12 Duct Work Flanges

All rectangular ductwork shall be flange joints. Flanges shall be of a proprietary type,
tested and certified for air leakage and deflection to DW/144. Certificates must be
submitted during the equipment submission period.
The proprietary ductwork flanges shall be roll-formed from zinc coated hot-dipped
galvanised sheet metal .Flanges shall be constructed with prefabricated flange
profile consisting of manufacturer provided integral sealant with corner joints inserted
into the end of the flange profiles and the whole frame shall be firmly secured
including the corner component. Gaskets strip shall comply with BS 476 Part 7,
Class 1 and ductwork sealant to BS 476 Part 7, Class 2 shall be applied at the
flange joints and corner joints respectively to ensure maximum leakage-proof. All
sealant used shall be fire proof and vermin proof, non-toxic and acceptable to the
Fire Services Department.

3.8.2.13 Turning Vanes

Turning vanes shall be provided for all abrupt changes in airflow direction. Provide
vanes, supported with bars perpendicular to blades, and set into side strips suitable
for mounting in ductwork, with dimensions as given in SMACNA HVAC Duct
Construction Standards, Figure 2-3.

3.8.2.14 Sound Attenuator

Sound attenuator shall be provided as required to match the noise criteria as per
Appendix B. Attenuator shall be straight as required.
Outer casings of rectangular attenuators shall be fabricated from not less than 22
gauges; lock former quality confirming to the structural quality as ASTM A-446 in
accordance with ASHRAE guide or SMACNA. Seams shall be longitudinal, lock
formed and mastic filled.
Interior casings of rectangular attenuator shall be fabricated from not less than 24
gauges perforated sheet confirming to the structural quality of ASTM A-446.
Filler material, except for reactive (no media) silencers shall be inorganic glass fiber
of a proper density to obtain the specified acoustic performance and be packed

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under not less than 5% compression to eliminate voids due to vibration and
settling. Material shall be inert, vermin and moisture proof.
Combustion ratings for the attenuator with acoustic fill shall be not greater than the
following when tested to ASTM E 84, NFPA Standard 255, or UL No. 723:
Flame spread Classification ………….20
Smoke Development Rating ………….20
The Direction of air flow through each attenuator shall be clearly marked on the
outer casing.

3.8.2.15 Air Flow Pressure Switch

Air flow pressure switch shall be provided in the supply air duct before the first
branch. The switch shall be linked with HVAC MCC through HVAC control panel in
order to switch off the standby unit if it is started simultaneously with duty unit. This
protection shall be applicable for hand and auto mode. The purpose of this switch
is to protect the supply duct from explosion due to high excess pressure.

3.8.3 Air Outlets and Inlets

3.8.3.1 General

Select all diffusers to provide uniform air coverage without overlap. Air velocity up to
a height of 1.8m above the floor shall be 0.13 to 0.25 m/s (25 to 50 fpm).
Noise generated by outlet or inlet at peak volume shall be such that room sound
pressure level does not exceed the value given in section -2 Appendix B. Room
attenuation; the sound power level reference to 10-12 power watts.
All volume and air pattern devices shall be fully adjustable from the face of the
diffuser, register or grille.
Size of all round flexible or rigid duct connections to diffusers shall be the same size
as diffuser inlet diameter.
Grilles, register and diffuser locations shall be adjusted to suit reflected ceiling
drawings, or site instructions. It is recommended that all grilles, registers, diffusers,
louvers be from one manufacturer.
All diffusers, grilles and registers shall be supplied completely factory powder coated.
Finish colour shall be to the approval of the Company. The interior of all grilles and
diffusers is to be factory painted matt black.
All supply and return grilles and diffusers will have opposed blade balancing dampers.
All will have foam rubber sealing band around the edge to seal to the structure. All
pivots will be round section, not of formed sheet, and not relying on a spring steel
locking wire.
Unless otherwise specified basic grilles and diffuser materials shall be Aluminium
extruded sections. Sections in the airstream shall be carefully selected to minimize
turbulence.
All grilles and diffusers shall be tested and rated in accordance with ASHRAE
Standard 70-72, and ISO 3741.

3.8.3.2 Linear Bar Grilles

Linear bar grilles shall be fabricated from aluminium, single/ double deflection core.
The core can be either welded into the cuter frame, or, where the grille is used in a sill
application, held in the outer frame by spring clips fixed to the core retaining bar.
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The outer frame shall be 35mm deep and shall have a visible flange 25.4 mm wide.
Mitred end caps shall be welded to give a near invisible joint. The grill shall be
complete with an opposed blade damper painted matt black, and shall be fixed with
universal mounting brackets. Both the damper and the fixing brackets shall be
accessible through the face of the grille.

3.8.3.3 Four-way Ceiling Diffusers

Ceiling Diffusers shall be multi cone giving 4 way horizontal discharges.
The three centre cones of the diffuser shall be manufactured from pressed aluminium,
with the remaining cones and the outer frame fabricated from extruded aluminium
welded at the corners to give near invisible joints.
The core shall be removable without the use of special tools, but for safety, shall be
fixed to the outer frame by a small length of chain.
The diffuser shall be complete with an opposed blade damper painted matt black. All
supply air diffusers shall be provided with an adjustable equalizing grid.

3.8.3.4 Wall Registers

Wall registers shall be double deflection fabricated from aluminium, the front vanes
being horizontal, the rear vanes vertical. This grille shall be complete with an opposed
blade damper painted matt black and adjustable from the face of the diffuser.
Both sets of vanes shall be fully adjustable without the use of special tools.

3.8.3.5 Circular Ceiling Diffusers

Circular ceiling diffuser shall be of aluminium construction with two concentric inner
spinnings.
The diffuser core shall be fully adjustable for vertical or horizontal air discharge, and
shall be removable without the use of special tools.
A flap damper shall be provided in the neck of the diffuser which is adjustable from the
diffuser face.

3.8.3.6 Linear Slot Diffusers

Linear Slot diffusers shall provide unobtrusive continuous air diffusion with a pleasing
aesthetic appearance. Hairline butt joints shall ensure clean unbroken linear runs for
active and dummy sections. Slot width shall be 16/20/25 mm.
The diffusers shall be complete with pattern control blades, fully adjustable from face
of diffuser through 180 degrees and shall be fitted with end caps at each end.
The diffuser members shall be constructed from high quality aluminium extrusions to
BS 1474 while the pattern control blades shall be of black rigid PVC.

3.8.3.7 Extract Air Louvers

Louvers shall be extruded Aluminium frame with Aluminium blades of not less than 2
mm thickness, and shall be firmly fixed so as not to vibrate. Unsupported blade width
shall not exceed 1800 mm.
Behind each louver shall be an insect mesh screen 76 x 6 mm made from 2 mm
diameter stainless steel wire. The screen will be clamped by a 20 mm frame and will
be firmly fixed to the outer edges of the louver. The frame shall be hot dip galvanized
after fabrication.

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The connection to the louver shall be flexible and shall ensure no duct load is
transmitted to the louver.
Louvers shall be provided with powder coated finish to the approval of the Company.

3.8.3.8 Sand Trap Louvre for Fresh Air Intake

Sand trap louvers shall have a double deflection inlet passage to separate sand from
incoming air by means of centrifugal forces.
Separation efficiency particle size 350-700 shall not be less than 90% at a face
velocity of 1M/Sec and not less than 70% at a face velocity of 2M/sec.
Sand trap louver shall be of aluminium construction, self cleaning and maintenance
free. The base of the louver shall have self emptying sand holes.
Pressure drop at 2 M/Sec average face velocity shall not exceed 120 Pascal.
Volume control damper and sliding washable aluminium filter shall be included.
Sand louvers shall be provided with powder coated finish to the approval of the
Company.
Behind each louver shall be an insect mesh screen 76 x 6 mm made from 2 mm
diameter stainless steel (316) wire. The screen will be clamped by a 20 mm frame and
will be firmly fixed to the outer edges of the louver. The frame shall be hot dip
galvanized after fabrication.

3.8.4 Duct Construction and Installation

3.8.4.1 General

All ductwork shall be constructed, reinforced, supported and installed in accordance

with HVCA or SMACNA "HVAC Duct Construction Standards - Metal and Flexible',
and the specification herein.
All supply and return ductwork within 4.5 m of the air handling unit, measured from
the unit along the duct, shall be minimum 1 mm ( 20 ga.) sheet metal or heavier, but
shall otherwise meet the pressure and seal classes.
Make all laps in the direction of air flow. Hammer down all edges and slips so as to
leave smooth finished surface inside the ducts.
All ducts shall be braced and stiffened and shall be tight so that they will not breathe,
rattle, vibrate or sag. Cross-break or transverse bead all rectangular ducts as per
HVAC or SMACNA standards.
Duct sealant such as mastic shall be manufactured by the approved manufacturer.
Brush joints with the compound before and again after assembly. Mastic sealant
shall be applied to all duct transverse joints and longitudinal seams.
Seal the bottom and side joints of fresh air ducts or plenums to be watertight.
Flexible duct connections shall be of Class 1, corrugated aluminium flexible duct
suitable for 1200C and 1.5 kPa and shall bear the 'building unit' label of Underwriters'
Laboratories. Flexible duct connections shall be insulated with 25 mm fibre glass
insulation with density of 24 kg/m3 complete with vapour barrier.
Bends in flexible ducts shall have centreline radius of not less than 1 1/2 x diameter.
Collars to which flexible ducts are attached shall be a minimum of 50 mm in depth.
Metal flexible ducts shall be attached using a minimum of three #8 sheet screws
equally spaced around duct. Ducts larger than 300 mm diameter shall have a
minimum of five #8 screws. Screws shall be located at least 12 mm from duct end.
Insulation and vapour barriers on factory-fabricated ducts shall be fitted over cone
connection and supple- mentally secured with a draw band.
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Generally more durable and noise-resistant sheet metal ducts are preferable to
flexible ducts in connecting ducts to diffusers or boxes. However, flexible ducts may
be used under the following conditions:
If shown on drawings to allow easy location of diffusers. Does not pass through
floors or fire walls and does not exceed 1 m in length. Flexible ducts shall not be
installed in inaccessible locations, such as above gypsum board ceilings unless
specific approval from the Company is obtained.
Where ductwork passes through a wall or floor, other than when a fire damper is
required, pack around the duct using a fire resistant material to ensure a sound and
air-tight joint. Cover the opening with sheet metal flange of the same metal thickness
of duct, overlap opening on four sides by at least 38mm.
Install ducts with fewest possible joints. Locate ducts, except as otherwise indicated,
vertically and horizontally, and parallel and perpendicular to building lines; avoid
diagonal runs. Install duct systems in shortest route that does not obstruct usable
space or block access for servicing the building and its equipment.
Battery rooms shall be supplied with conditioned air at low level through droppers
with VCD for each dropper, motorised control damper (MCD) shall be provided in
main supply duct. The actuator for supply duct of the battery room shall be designed
for zone 1, T4 rating, Gas Group IIB/IIC. Exhaust shall be from the higher level from
the opposite side as describe in specialist areas battery rooms in section-2.

Install ducts with a clearance of 25mm (1 inch), plus allowance for insulation
thickness.
Locate all sheet metal ducts where shown and size as shown. If changes of size or
location of ducts are found necessary because of building construction, make a
specific proposal for review by the Company engineer prior to proceeding with the
change.
Make changes of direction of horizontal ducts with elbows having an inside radius
not less than the width of the duct, Make change of direction from horizontal to
vertical duct with elbows having an inside radius equal to the depth of the duct.
Where this is not possible due to the building construction, use turning vanes.
Provide access ports at convenient locations in all main ducts and main branch take
offs with airtight covers and extension sleeves through insulation to allow air meter
readings. Access ports shall be similar to 32 mm round openings as approve by the
company.
Provide flexible connections as specified at each building expansion joint, air
handling unit and fan duct connection.
Paint visible internal surface behind each grille or register flat black.

3.8.4.2 Duct supports

General: Install rigid round, rectangular, and flat oval metal duct with support
systems indicated in SMACNA “HVAC Duct Construction Standards”, Tables 4-1
through 4-3 and Figures 4-1 and 4-8 or DW/144 standard, tables 15 and figure 68
through 77.

Support horizontal ducts within 600 mm of each elbow and within 1200 mm of each
branch intersection. Support vertical ducts at a maximum interval of 4800 mm and at
each floor.

Upper attachments to structures shall have an allowable load not exceeding one
fourth of the failure (proof test) load, but are not limited to the specific methods
indicated.
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Vapour barriers used in building construction shall not be punctured.

Install concrete insert prior to placing concrete or install powder-actuated concrete

fasteners after concrete is placed and completely cured.

The ducting shall be supported from a structurally sound part of the building by
galvanized steel rods and galvanized steel angle brackets. The support angles, and
rods shall be of adjustable type.

The ducting shall not rest on the insulation at support locations. At the support
locations suitable insulated spacers of neoprene make shall be provided so that the
insulation does not rest on the supports. The spacers shall be minimum 25 mm in
excess of insulation depth and shall be securely fixed to steel support brackets.

3.8.4.3 Cleaning
Protect ductwork against entry of foreign matter during construction. Remove all dirt
and foreign matter from the entire duct system and clean diffusers, registers and
grilles before operating fans.
Provide temporary capping of ductwork to prevent entry of foreign matter during
construction.
Clean duct systems with high power vacuum machines. Protect equipment which
may be harmed by excessive dirt with filters, or bypass during cleaning. Provide
adequate access into ductwork for cleaning purposes

3.8.4.4 Test Holes

Test holes shall be provided wherever necessary for effective balancing and testing,
whether these provisions are shown in the Drawings or not. Test holes shall be of 25
mm diameter and fitted with an effective removable sealed cap. Test points shall be
provided for all dampers and items of equipment to enable fan duties and items to be
assessed and for the commissioning of the system.

3.8.4.5 Testing, Balancing and Commissioning

Adjust volume control devices as required by the testing and balancing procedures
to achieve required airflow. Refer to Document, Testing, Adjusting, and Balancing of
HVAC for requirements and procedures for adjusting and balancing air systems.
Provide notice of testing to the Company in accordance with Contract requirements
so that, where he deems necessary the Company representative shall witness the
test. The test rig and all necessary blanks for the purpose of sealing the ductwork
under test shall be provided, and blanks shall be removed after the test has been
approved for each section of the ductwork.
Constant and variable air volume boxes or any other ancillary items of equipment
which may be liable to damage by the test pressure shall be isolated during the test
and all necessary precautions shall be taken. Any damaged equipment shall be
replaced.

3.8.5 Duct Insulation and Liner

General: All insulating material shall be non-combustible as defined in the NFPA
220 and shall have a frame spread rating of not more than 25 and a smoke
developed rating of not more than 50 as defined in UL standard test method of fire

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hazard classification in building materials list or approved equal. The completed

installation shall confirm to all applicable requirements of NFPA.

3.8.5.1 Thermal Insulation

Thermal insulation shall be provided on all surfaces operating with a surface
temperature below that of the surrounding air. When the surface temperature is
below the dew point of surrounding air, an impervious vapour barrier shall encase
the outer surface of insulation.
Ductwork shall be insulated with 50 mm thick, rigid glass fibre slabs/ blanket, or pre-
formed sections, minimum density 48 kg/m3 and thermal conductivity not greater
than 0.04 W/moC, faced with aluminium foil –Kraft laminated vapour barrier securely
fixed directly to the metal ductwork with adhesive and wrapped with canvas cloth and
coated with 2 coats of Foster & equals.
Joints between sections shall be covered with 75 mm wide, plastic contact adhesive
tape fixed with a tack coat of adhesive on the aluminium surface. All raw edges shall
be filled with reinforced Foam seal.
Ductwork external to buildings or in Plant Rooms shall, in addition to both the above,
be finished and protected with 0.9 mm, 'hammered', aluminium sheeting. All joints
shall be overlapped and secured with pop rivets. Bands shall be neatly formed and
fitted at all termination points with segments and tees gartered.
Vapour barriers shall be continuous over thermal insulation, including branch
connections, flanges, hangers and like equipment. Where insulation is terminated,
ends shall be fully sealed. Adhesive and sealers shall be approved by the company
may be used.
Access panels in ductwork shall be fitted with purpose-made rigid fibre, removable,
covers with quick release bands or fasteners.
Damper, test hole and instrumentation, connections etc. insulation shall be neatly cut
and sealed to allow permanent access.

3.8.5.2 Acoustic Insulation/ Liner

Sound attenuators shall normally be used at all times. However, there may be an
occasional need for a liner.
Materials
Duct liner shall be fibreglass blanket type with black acrylic fire-protective microbial
resistive coating on airstream side. Liner shall be asbestos-free and environmentally
friendly. The material to be used for duct lining shall be 25mm thick resin bonded
fibre glass having a density of 48 Kg/m³ & covered with 0.5 mm thick perforated
aluminium sheet. Thermal conductivity shall be a maximum of .035 W/m °C at 24°C
mean temperature. Temperature limit shall be a maximum of 122°C. Fire hazard
classification, as rated per UL 723, shall be a maximum of 25 for flame spread and
50 for smoke developed or in accordance with BS 476, Part 4. Surface burning
characteristics shall conform to NFPA 255 requirements and be tested per ASTM
E84. Sound absorption coefficients shall be in accordance with ASTM C423 under
F25 mounting.

Both adhesive and sealant shall be recommended by the Manufacturer for the
purpose and classified Class 1 flame spread in accordance with BS 476, Part 7.

Installation
Installation shall follow the manufacturer's recommendations.

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Adhesive shall be applied with 100% coverage of the sheet metal surface prior to
bonding the glass fibre.
In addition, the insulation shall be secured to the sheet metal by mechanical
fasteners. Fasteners shall be adhered, not spot-welded, to the ductwork and pins
shall be turned over in the direction of airflow. Fasteners shall be fixed at not more
than 350 mm centres, shall start within 50 mm of open edges, i.e. sheet metal joints,
and within 75 mm of corners and longitudinal butts.
At open edges, the glass fibre shall be cut back and the facing turned under. The
turned facing shall be secured on both sides of the glass fibre by the fastener. At
corners and longitudinal butts, the glass fibre shall be cut back and the facing turned
under. At lateral butts, the upstream glass fibre shall be cut back and the facing
overlapped on the facing of the downstream slab.
Sealant shall be applied with 100% coverage of joints at edges, corners, longitudinal
butts and lateral butt facing overlaps. Sealant shall also be applied to repair all
facing cuts and tears.
Lateral and longitudinal butts shall be allowed only where the duct side is greater
than the glass fibre slab standard size.
The liner shall be fixed to ductwork sections in a sheet metal workshop, not in situ.
Lined sections of ductwork shall be subject to the Company's inspection on site
before installation and shall require the Company's approval, in writing, in position
prior to closing up.

3.8.5.3 Adhesive and Fastener Materials

3.8.5.3.1 Liner Adhesive

Liner adhesive shall comply with NFPA 90A and ASTM C 916. Adhesives shall be
non-oxidizing, water based and asbestos-free. Adhesive service temperature limits
shall be a minimum of -18°C to 82°C. Flammability: 100 °C (min). Water vapour
permeance at 0.031 dry film thickness (DFT). Fire hazard classifications, as rated
per UL 723, shall be a maximum of 10 for flame spread and 5 for smoke developed.
Surface burning characteristics shall conform to NFPA 255 requirements and be
tested per ASTM E84.

3.8.5.3.2 Mechanical Fasteners

Mechanical fasteners shall be galvanized steel, suitable for adhesive attachment,
mechanical attachment to duct.
Provide fasteners that do not damage the liner when applied as recommended by
the manufacturer that do not cause leakage in the duct, and will indefinitely sustain a
50 pound tensile dead load test perpendicular to the duct wall. Fastener pin length
shall be as required for insulation thickness without projecting more than 4 mm into
the air stream. Adhesive for attachment of mechanical fasteners shall comply with
the “fire hazard” classification of the duct liner system.

3.8.6 Sealing Materials

The term “sealant” used here is not limited to materials of adhesive or mastic nature,
but also includes tapes and combinations of open weave fabric strips and mastics.
Sealant materials shall be with the type of joint to be sealed. Tape of an approved
type shall be applied over the sealant, but shall not serve as the primary air seal.

Joint and Seam Tape: 50 mm wide, glass-fibre fabric reinforced.

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Tape Sealing System: Tape sealing system shall consist of a woven-fibre tape,
impregnated with a gypsum mineral compound and a modified acrylic/silicone
activator to react exothermically with the tape to form a hard, durable, airtight seal.

Joint and Seam Sealant. One-part, non sag, solvent-release-curing, polymerized

butyl sealant complying with FS TT-S-001657, Type I; formulated with a minimum of
75 percent solids.

Flanged Joint Mastics. One-part, acid-curing, silicone elastomeric joint sealants,

complying with ASTM C 920, Type S, Grade NS, Class 25, Use 0.

3.8.7 Fire-Stopping
Fire-Resistant Sealant: Provide one-part elastomeric sealant formulated for use in a
through-penetration fire-stop system for filling openings around duct penetrations
through walls and floors, having fire-resistance ratings indicated as established by
testing identical assemblies per ASTM E 814 by Underwriters Laboratories or other
testing and inspecting agency acceptable to authorities having jurisdiction.

3.8.8 Silencers (Sound Attenuator)

Silencers shall be installed when required to achieve the specified noise levels.
Silencers shall be installed in locations as indicated on the contract drawings.

At shop drawing stage, the contractor will undertake calculation for every unit and
every area and determine the insertion loss required to meet the stated noise
criterion. Supply and return duct noise must be considered.

Materials of construction shall be hot dip galvanized sheet metal and mineral fibre
acoustic fill which is inorganic, inert, moisture and vermin resistant. Silencers shall
be so constructed as to prevent erosion of the acoustic fill.

The silencers shall incorporate a removable panel which provides complete access
to all internal surfaces for cleaning and also permits removal and replacement of
acoustic fill.

Silencers shall be factory made, and shall have available certified test data
concerning insertion loss. This must be available when required, in advance of
ordering units.

The static pressure loss of any required silencer must be considered in air handling
equipment original selection.

Silencers shall be flanged to exactly match the adjacent ductwork in which they are
to be installed.

3.9 Power and Automation Control

3.9.1 General

This design criteria along with specifications, practices, and standards referenced
herein provides the basis for engineering and design of the HVAC control systems.
HVAC control and alarm systems shall be in line with the HVAC vendor's standards.
HVAC control systems should at least include the following:
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(a) Temperature control

- For constantly manned rooms (e.g. control room, shift supervisor room);
- For certain rooms which are less frequently used (e.g. meeting rooms, mess
rooms etc.);
- For equipment rooms and buildings (e.g. instrument auxiliary room, electrical
auxiliary room, computer room, and electrical substations.
(b) Humidity control
- For all rooms and buildings.
(c) Pressure control switch
- For main duct of each AHU after motorised damper and before supply
plenum box. The sensor shall protect the duct from over the pressure. The HVAC
control panel shall trip the AHU supply motor if the duct pressure is accessed more
than 10 percent of the design working pressure.

Control systems shall normally operate in automatic mode but manual operation
shall be possible.
HVAC alarms shall be individually displayed on local HVAC panels. Common HVAC
alarm signals generated by the HVAC control system and displayed on the DCS
screen in the main control room shall be routed either via potential-free contacts and
interface boxes or via software links.
Control signals coming from an HVAC control system cabinet and going to an HVAC
motor control centre (power) cabinet shall pass via an interface box. The HVAC
control/alarm cabinet and the motor control centre (power) cabinet shall be
physically separated. For central air handling units, both cabinets should be located
in the HVAC machine room.

3.9.2 Design
The HVAC Control system & all electrical components shall be designed and
installed per the following Design General Specifications:

Electrical Design Guidelines, Power, Control, Lighting and Earthlings Cables,

Instrument and thermocouple Cables, Design General Specification - System
Cables, Design General Specification Instrument Design Criteria on Process Units.

Each building shall have a HVAC power and control panel. This panel shall be
located inside the AHU room. The suitable panel shall be provided with run/off/trip
indications and auto/manual/off switches and provisions to send fault signal to the
Central control room. The control system shall be designed such that each
mechanical system will be able to operate under stand-alone control. As such, in the
event of a network communication failure, or the loss of any other controller, the
control system shall continue to independently operate under control. The
appropriate control system shall be so designed to meet the requirements and
operation needs of the building operation & management team and the operation
requirements of the end users in building(s).

The HVAC Motor Control Centre (MCC) shall be in full compliance with Company
Specification of Low Voltage Switchgear and Controls. Installation of this MCC shall
be in accordance with Electrical Design Guidelines Specification.

The HVAC system of each building shall be provided with a dedicated PLC based
control system.

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The PLC shall be directly interfaced with the local MCC for control of electrical HVAC
equipment.

In addition the PLC shall, via suitable interface facilities, control all field mounted
HVAC equipment and be capable of receiving all field instrument and equipment
control inputs.

The control system shall be capable of operating during the maximum specified
ambient temperature and humidity without failure.

Operating pilot and indicating devices have to be situated on the front panel for easy
reading.

The HVAC control system shall be consist of the following but not be limited as
below

• LCD screen for master controller

• Power lamps.

• Panel fluorescent light with door switch.

• Panel Lamp test facility.

• Panel Ventilation fan with filter.

• Ambient temperature indicator.

• Open/close indication for each motorized shut off damper and fire damper.

• Air flow failure.

• Chilled water flow failure.

• Chilled water supply/return temperature indication.

• Run/trip indication for each heater battery.

• Interlock of AC system and each ventilation system to station alarm facilities.

• Fire alarm panel interlock for each AC and ventilation system and fire dampers
shut down.

• Separate circuit breakers for various HVAC equipment.

• Duty selector switch for AC units, twin fans, chillers and pumps.

• Hand/off/auto selector switch for each A.H. unit and fan.

• Auto changeover of AC units in the event of failure of running units to stand by

equipment.

• Ventilation system operation including pressurization, temperature and humidity

control

• Ventilation system starting/stopping sequences.

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• Indication of running conditions e.g. on/off, fault, status, open/closed, etc., for all
applicable types of equipment (fans, pumps, chillers, heaters, dampers, etc...).

• Alarm grouping and indication

•All test and maintenance operations.

• Pressure switch for filters.

• HVAC control panel shall be interlinked with fire and gas panel.

• Additional 20% I/O points shall be provided in HVAC panel.

• For DX system refer to control schematic diagram* as shown in figure no A16

All the above mentioned points shall be shown on the master graphic screen. Full
graphics screen shall be visible on the outer face to the panel.

“Chiller fault” and “room temperature high” alarms shall be provided in the HVAC
control panel and same shall be repeated on the Distributed Control System (DCS).

The HVAC control panel shall be interfaced directly with the DCS of the control room
for communications.

The HVAC control panel shall be interfaced directly with the F&G system for area
protection, isolation and shutdown purposes. The HVAC system shall initiate
relevant shutdown actions on receipt of F&G inputs as required and confirm such
actions to the F&G.

Access and manual control actions for the HVAC control system shall be via
operator DCS interfaces facilities (if required)

HVAC Control Software Package shall be handed over to Company for future use
and Company personnel shall be trained for using the above Software.

* The diagram is showing minimum requirement for HVAC DX system. Additional

requirement shall be added to the diagram for any specific project if it is required.
Refer to Appendix A (Figure A16).

3.9.3 Functional Description of Control System:

Air conditioning shall be controlled by thermostat (heat / cool, humid), temperature
(cool/heat) controller in response to the signals from return air duct sensors. A
humidity controller, on receiving high humidity signal from the return duct humidity
sensor, shall over ride temperature controller and operate cooling cycle to carryout
dehumidification. In the event of temperature dropping below set point, the
temperature controller will bring in the heaters. Compressors and heaters shall be
interlocked with fan starters and airflow switches to shut off at no airflow conditions.
All fire dampers need to be open for AHUs and ventilation fans to start. A fire alarm
signal shall shutdown the full HVAC system.

The unit control systems shall be of the electronic DDC or PLC type capable of
providing the degree of thermostatic and/or humidity control specified.

The HVAC control panel shall be able to give command, status and alarm of the
following:-

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• Ambient temperature

• Building temperature

• Temperature set point

• Supply air temperature

• Mixing air temperature

• Temperature differential or sensitivity

• Ambient Humidity

• Building Humidity

• Humidity set point

• Humidity differential or sensitivity

• Running Units

• Number of compressor running

• Extract fan running

• All damper open and close

•
• Valves
•
• Pumps
•
• Pressurization units
•
• Chemical dosing system
•
• Pressure duct switch

The control parameters are to be indicated on a LED or LCD display being part of
the controller or separate.

Detailed sequence of operation and control/power wiring diagram for the control
system shall be submitted by contractor for employer/engineer approval.

The control system shall incorporate all necessary safety interlocks for the
successful operation of the mechanical plant and systems. All of the individual
control elements shall be provided by the same manufacturer.

3.9.4 Material
(a) Direct Digital Controller (DDC)

(i) Each controller shall operate as a standalone unit capable of performing its
specified control responsibilities independently of other controllers in the network.

(ii) Local keypad and display shall be provided for local viewing and operation.

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(iii) Power Fail Protection – All system set point, control algorithm and other
programmable parameter should be stored such that power failure of any duration
does not necessitate reprogramming the DDC controller.

(b) Set point potentiometers shall be housed in a robust casing of high impact
plastic suitable for the decor of the area in which they are mounted, the control
knobs shall have markings in °C over the band specified and the knob shall be
removable enabling the setting to be fixed and enclosed under a dummy knob,
rendering it tamperproof.

(c) Temperature sensors shall be of the resistance type using nickel based
element and shall be accurate to 0.5°C, over the range of 0°C to 60°C. The sensor
resistance shall be compatible with the measuring bridge of the matching control
box.

For immersion temperature sensors, sensors shall be provided with immersion

pocket. The sensing range shall be of 0 °C to 120 °C.

(d) Humidity sensors shall be of the thin film capacitor or plastic strip type and
cover the range specified for control plus 02 % above and below.

(e) Duct sensors shall incorporate a 200mm long non-corrodible tube with the
sensing element mounted in a protective housing at the end of the tube.

(f) Step controller shall provide the required number of operational steps and
shall comprise a series of cam operated micro switches operated by means of an
electric motor or shall comprise the required number of voltage dependent relays
switching in sequence with the output voltage signal from the control box. The cut in
points and switching differentials shall be fixed at equal proportions of the operating
range.

(g) Room Thermostat

Provide room thermostat with flame retardant plastic (ABS) casing. The room
thermostat shall be provided with set point adjust dial for remote set point
adjustment. The temperature range shall be between 12° to 35°C.

The cooling &heating thermostat shall be provided with 3 position slide switch for
manual control of fan speed apart from auto mode position and cool/heat change
over.

The room thermostat shall be provided with momentary override button to

circumvent day/night programming.

The thermostat shall have LCD display and key pads and shall conform to current
industry standards.

(h) Control Valves

Provide 2 way /3 way modulating control valves for all chilled water coils. The
response time shall not be more than 45 second. Provide position indicators on
valves and pilot positioners on sequenced valves.

Valves trim and stem: Stainless Steel.

Packing: Spring loaded Teflon, self adjusting.

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Select valves to have equal percentage characteristics. Size valves operators to

close valves against pump shut off head.

(h) Cabinets of control panel

Cabinets shall be constructed from form- 2 (Non-compartmentalised) thick sheet

steel panels built up on rolled steel or boxed sheet steel section framework, and
shall have continuously welded butt joints. All required holes and cutouts shall be
done at the factory.

The cabinet shall be divided internally with sheet metal webs to separate low voltage
equipment from instruments and control equipment and to prevent overheating.
The control panel shall have adequate access doors to ensure ease of maintenance
of equipment. Access doors shall have concealed hinges, stops and interlocks
where required, and a dust excluding gasket contained in a rebate. Hinges shall be
strong and may be taken off only by the use of special tools.

The DDC enclosure shall be with following specification:

- Paint shade : RAL 7035(internally and externally)

- Mounting plate colour : RAL 2000
- Enclosure Thickness : 2 mm
- Paint thickness : 70-100 Microns
- Earth Busbar : Earth Strip Busbar

Door handles shall be the rotating type closing onto ramps, of approved pattern,
finished in a black, hard wearing non-conductive material.

After fabrication, steelwork shall be cleaned, zinc sprayed and stove enamelled with
one primer coat, two undercoats and one finishing coat, the surface being rubbed
down after each coat. The finish color shall be light grey or company approved.
The operating handles of each protective device shall project from cut outs in the
front door and all switching and protective devices shall have clear on / off
identification.

3.9.5 Control and Monitoring Philosophy for Direct Expansion System.

The HVAC system serving the building shall be integrated with FCS/DCS, via HVAC
DDC panel.
The room temperature control is achieved by means of temperature controller
mounted in the HVAC control panel (DDC) located indoor. Return air duct
temperature sensor provides the actual return air temperature input to the
temperature controller. Based on the return air temperature and the set temperature,
the controller gives the signal for the compressors of respective condensing units to
be switched On/Off depending on the load conditions to maintain the room
temperature conditions. To meet the inside conditions during winter and after/during
dehumidification, the controller provides the controlled analogue output signal to
operate AHU heater and maintain the design room temperatures.
In event of increase in relative humidity the controller shall switch on the
compressors for dehumidification of supply air by over riding the temperature set
point.

Air flow fail switch & dirty filter switches are provided on the AHU across the supply
air fan & across the filters to detect the air flow and cleanliness of the filters. The
switches are wired to provide visual indications on the HVAC control panel for

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“airflow fail” and “dirty filter”. Motorised damper shall be installed for AHU supply and
return air connections to isolate the standby AHU. Power to the HVAC equipments
shall be provided by HVAC MCC located in switchgear room building.
The supply air duct shall be connected to battery room through a dropper at a height
of 300mm from bottom of the finish floor. Motorized fire damper shall be placed in
the supply air duct at the entry of the room.
AHU comprises of pre filter, bag filter, cooling coil, electrical heater, and supply fan
with constant speed motor and interconnected to DX system with all necessary
control items.
The AHU shall have differential pressure switches for Pre filter, bag filter, air flow
failure, On/Off type damper actuator in supply air duct, temperature & humidity
sensor in the return air duct and temperature & pressure sensor in the supply air
duct. Temperature & humidity sensor shall be provided for ambient air.

3.9.5.1 AHU Fan Start/Stop & Monitoring

At the start up of the system in “AUTO” mode, HVAC control panel will command the
fresh air motorized damper actuator to open with the specific time delay of 30
seconds which is connected in the inlet of the fresh air intake of the AHU. After
receiving the damper’s open status feedback from the damper, then the HVAC
control panel will command duty AHU fan (blower motor) to switch “On”, provided the
time schedule is “On” and interlock with standby unit.
Also at the start up of the system in “Auto” mode, HVAC control panel will command
the duty AHU supply and return air damper to open with specific one minute time
delay. After receiving the damper’s open status feedback from both the damper
(after 30 seconds), then the HVAC control panel will command respective AHU
supply fan (blower motor) to switch “On”, provided the time schedule is “On” (a
weekly time scheduler’s provided to switch off/on automatically as and when
required based on working hours). HVAC control panel continuously monitors AHU
supply fans through run status and fault status. Upon receiving fan fault status,
HVAC control panel will command to close the return and supply air damper of
working AHU and generates an alarm and displays in HVAC control panel and
FCS/DCS screen. HVAC control panel will command standby unit to start with the
same sequence as described above.
If HVAC control panel doesn’t receives damper open status feedback in specified
time delay (one minute), damper fail to open alarm will be generated and standby
AHU will start upon receive of the damper open status along with related equipments
associated with it.
The differential air pressure switches are used to monitor individual filter bank on the
condition of the filter, which is fixed across each type of filter and in turn sends the
feedback for HVAC control panel via a volt free contact (VFC). Interface between the
HVAC control panel and power panel occurs via volt free contacts provided in the
power panel and the same will be shown in the HVAC power panel drawings.
An airflow switch is mounted across the AHU supply fan. The contact in the airflow
switch closes when the pressure drop across the fan exceeds the setting
(adjustable) on the switch. This airflow switch is connected to a digital input in the
HVAC control panel. If there is “No” air flow signal from air flow switch, even after the
receiving the “On” Command from HVAC control panel for 30 seconds, HVAC
control panel generates an air flow fail alarm and turns off the duty unit and provides
a start command to stand by AHU to start along with related equipments associate
with it. The HVAC control panel commands the condensing uint to start/on base on
common return temperature set points and monitors its run and fault status through
a volt free contact continuously. If duty condensing/package unit fails to start within
one minute, HVAC control panel generates fail alarm and turns off the duty unit and
provides a start command to standby unit to start along with related equipment
associate with it.
The AHU(s) shall not be in running condition if any of fire smoke dampers are in
close position.

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3.9.5.2 Temperature Control

The common return air temperature shall be maintained precisely at the desired set
point (programmable) by controlling and modulating the capacity of the compressors
in condensing/package unit. The duct mounted common return temperature &
humidity sensor measures the temperature and humidity in the return air, feedback
to HVAC Control panel to maintain the set temperature and humidity. Supply duct
temperature sensor is installed in the common supply duct to monitor/control the
duct temperature. Heater(s) will be controlled by return air temperature and humidity
sensor in return air duct.

3.9.5.3 Alarm Monitoring

• In the following events:
• If the AHU/PAC filter choke, an alarm (through HVAC control panel) will pop-up on
the operator terminal (FCS/DCS).
• If fire/smoke detection in particular zone, a common volt free contact digital input
will be relayed to HVAC control panel by F&G panel and in turn HVAC control
panel shall turns off all air conditioning equipments and its associated damper
actuators. The battery room extracts ventilation fans shall be switched off.
• For manned building, If hydrocarbon or H2S or any gas detection a common volt
free contact digital input will be relayed to HVAC control panel by F&G panel and
in turn HVAC control panel shall close off air tight damper in the fresh air intake,
then send stop command to the supply fan via a volt free contact (VFC) and turns
off all air conditioning equipments and its associated damper actuators. The
battery room extracts ventilation fans shall be switched off.
• For unmanned building, If hydrocarbon or H2S or any gas detection a common
volt free contact digital input will be relayed to HVAC control panel by F&G panel
and in turn HVAC control panel shall close off air tight damper in the fresh air
intake, then the HVAC system will continuing running in recirculation mode. Also
the HVAC control panel shall turn off both extract fan and close the motorised
damper for the battery room.
• Pressure sensor shall be provided in the main supply duct to monitor the duct
pressure. The trip single shall be sent to the supply fan in case the pressure
increase more than allowable limit (10 % of maximum pressure).

3.9.5.4 Change Over Philosophy

Cyclic change over between duty and standby AHUs along with respective zone,
battery room extract fans, condensing units and supply fan motors in the same
AHU/PAC is programmed for 7 days change over. The same shall be subjected to
168 running hours of the units.

Air Handling Unit/Package Uint

The fresh air damper shall be remained always open except during gas detection as
above.

Battery Room Extract Fan

The motor control centre serving the battery room exhaust fan has a "HAND-OFF-
AUTO" switch and transmits the “Auto” position to the HVAC control panel. The
HVAC control panel commands the duty extract fan to turn “On” provided time
scheduler is programmed and turned on. The overload trip and run condition of the
motor is monitored at the HVAC control panel via a volt free contact from the MCC.
The motorised volume control damper (MVCD) is fixed in the supply duct which is
feeding for battery room will always be open if any one of the battery extract fan is in
‘“On” status. If HVAC control panel doesn’t receives damper open status feedback in
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specified time delay (one minute), damper fail to open alarm will be generated to
FCS/DCS through common alarm and in turn HVAC system to be tripped.
Upon receiving a duty exhaust fan over load trip alarm, HVAC control panel
commands standby exhaust fan to “On” and generates a trip alarm which is
displayed in operator’s terminal. Individual DDC controller fail status signal will be
sent to FCS/DCS through a volt free contact.

In case of failure of both the explosion proof battery extract fan and/or motorized
volume control damper is not openning, then HVAC control panel shall send a signal
to UPS to inhibit the boost charging of the batteries.

3.9.5.5 Motorized Fire and Smoke Damper (MFSD)

The motorised fire and smoke dampers shall be provided in the supply and return
ducts as per project specifications. The MFSD will be controlled by DDC. Gas and
fire/smoke signals from fire and gas system shall be separate.

3.9.5.6 Maximum Allowable Running Time for Motorised Dampers

The table below to be adhered for the motorized dampers
Location Opening time Closing Time Remarks
(Seconds) (Seconds)
Type of damper
Supply damper After the 30 30
AHU

Return damper Before the 30 30

AHU
Fresh air In the fresh 10 2 High integrity damper as
air intake per EN1751
Modulating damper Fresh 5 5 This is used for lab and
air/supply/ret other applications*
urn
Battery room damper Main supply 10 5
duct for
battery room
Fire smoke damper Supply and 15 5 To be located where is
return duct duct crossing a wall or
entering/exist the building
Table 4
* For this type of application in a sour project, both dampers [modulating and high
integrity dampers]

3.9.6 Standards Control Interlocks

Unless otherwise specified the following equipment interlocks shall be provided:

a) Provide timers in the control circuits of all pumps to enable the pumps to
continue to run for a period after such-down of cooling plant.

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b) On plant start up and shut down operation, control circuits shall be arranged for
staggered switching of motors to avoid simultaneous large electrical loads being
imposed on the power cabling and power plants.

c) Under normal operating conditions, the extract fan starters shall be interlocked
with their respective supply fan starters and stop locks.

d) Humidifiers and electric heater batteries shall be interlocked with their

associated supply air fan to shut down the humidifier and electric heater battery
when the supply fan stops, or on power failure.

e) Fresh air inlet and discharge dampers shall close on normal plant shut down and
power failure. Operation from smoke detectors shall be as specifically required
by the local fire panel, or as per the dictable of the fire alarm and control system.

f) On full fresh air plants the air inlet dampers shall open before the fan can
operate, by use of damper motor end switches.

g) Where duty and stand-by pumps are provided, the selected duty pump shall
start and operate as required. Should the duty pump fail to start, a fault alarm
shall be given and the stand-by pump, after a pre-set period, shall operate. The
same automatic change-over sequence shall apply should a pump fail during
normal running.

h) When electric heating batteries and cooling coils are to be operated in sequence
a dead zone shall be provided between each sequence.

i) Fire dampers shall be equipped with limit switches in order to shut down the
appertaining A/C ventilating systems as well as to close the appertaining fire
dampers of the above A/C ventilating systems automatically in order to prevent
spreading of fire or smoke through the building (appertaining system means all
systems within the same fire zone).

3.9.7 Alarms on Local Control Boards

In general the following alarms shall be provided:

 Fire damper tripped.

 Air filter dirty.
 Failure of electrical humidifier.
 Overheating of air heater.
 Airflow failure.
 Temperature limit exceeded.
 Freezing danger (DX-coil).
 Refrigeration unit disturbed.
 Important single alarms and group alarms shall be provided on single terminals
and are to be cabled to the central, remote control and alarm system.

3.9.8 Building Management System (BMS)

The Building Management control system (BMCS) shall consist of the following
elements minimum unless otherwise specified.

Microcomputer based remote control panels interfacing directly with sensors,

actuators and environmental delivery systems (i.e., HVAC equipment, plumbing and

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lighting systems, etc.). The BMCS shall interface with the automation panels subject
to company approval.

The system shall have an inbuilt spare capacity of minimum twenty percent at all
levels of control and network to allow for future expansion.

Communication networks to allow data exchange between remote panels and the
central Building Management computer.

One personal computer (PC) based central and associated operator station(s) and
software functioning as the primary operator interface for the BMCS.

Electronic and electric controls for all items indicated on drawings and described
hereinafter including sensors, control valves and thyristers.

Submittals, data entry and electrical installation, programming, interfacing with other
systems, start up, test and validation, instruction of Owner's representative on
maintenance and operation, as built documentation, and system warranty.

The hardware /software used shall be an open–protocol system, proposed by the

Tenderer and subject to Engineer’s approval.

The BMS shall be a digital microprocessor based system of the latest proven
technology. It shall incorporate microprocessor based general purpose Direct Digital
Controllers (DDC) at the field level which shall interface directly with sensors,
actuators, pneumatic and electric controls, etc. The DDCs shall be provided on
standalone basis and individually for each area. Each DDC shall have real time
clock, EEPROM, RAM, PEER to PEER communication and shall be provided with a
Portable Operator Terminal. The BMS shall incorporate at the automation level
System Controllers which shall have, but not limited to, the following functions:

3.9.9 Electrical Connections

All electrical power, control cable and wiring associated with the air conditioning and
ventilation system including all connections between control panels, valves, sensing
probes and other like items shall be supplied, installed and connected up as part of
Contract.

The cabling and wiring system shall comply with the requirements of the relevant
Clauses of electrical Specification.

Electrical sockets for maintenance works and water connection for cleaning of
condensers and water tap with hose adaptor for cleaning air filters are to be
provided.

Cables and wiring shall comprise either PVC/SWA/PVC, laid in cleats or

trenches/tray work, or PVC drawn into galvanized conduits and trucking for control.
Cables and wiring for Power shall, however, be XLPE insulated.

Final connections to electric motors and all other items of plant subject to movement
and vibration shall comprise flexible cable in flexible conduit. Field isolators shall be
provided for all AC and ventilation equipment.

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3.9.10 Electrical Power Supply and Electrical Safety

3.9.10.1 Electrical Power Supply

The electrical power supply for vital HVAC systems (units) shall be either AC
interruptible maintained or AC uninterruptible maintained, as follows:

vital HVAC control systems and local panels: AC uninterruptible maintained

electrical supply

vital re-circulation air handling units (including AC interruptible maintained

ventilators, pumps and chilled water system): electrical supply

3.9.10.2 Electrical Safety

The type of protection for the electrical apparatus installed shall comply with the
requirements defined in IEC 60079-14.

3.9.11 Start-up and Commissioning

After completion of the control system installation, the control supplier shall regulate
and adjust all thermostats, control valves, damper motors, etc. and place them in
complete working order subject to the approval of the Company.

Complete instructions shall be given to the operating personnel. Such instructions

shall be exclusive of the time required for regulating and adjusting.

3.10 Cold Room

3.10.1 General
Rooms with typical "Cold Room" construction are installed in catering areas for food
storage. Cold Rooms served by refrigerated forced draft coolers are generally
controlled down to 0°C. Cold room units shall comprise an outdoor air-cooled
condensing unit and matching evaporator unit with interconnecting refrigerant pipe
work. Internal room dimensions shall meet the requirement to store food items.

3.10.2 Room Construction

(a) Walls:

The rooms shall be constructed on insulated panels fixed to the structural floor slab
of the Building. An insulated floor shall be provided to the rooms. The rooms shall
meet or exceed the current food hygiene regulations.

Stainless steel components shall be "com steel" type 302 grade having a smooth
No. 4 satin finish. A P.V.C. coating protection shall be retained until commissioning
and blemished or scratched surface will not be accepted.
Aluminium components shall be clear anodized after extrusion. All steel work shall be
hot dipped galvanized after fabrication. Where the cutting is required sections shall
be removed from site and re-galvanized before final installation.

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The Cold Room walls shall be composite sandwich panels comprising self-
extinguishing expanded polystyrene foam having the following specification.
Walls & Ceilings Floors

Density 16 kg/m3 24 kg/m3

Thermal 0.036 w/mk 0.034 w/mk

Conductivity
Permeability 580 UG/m2 460 UG/m2

Compressive 85 kPa 135 kPa

Strength

Walls and ceilings insulation shall have all exterior and interior surfaces clad in 0.6mm
thick off white colour bond. The cladding shall be glued under pressure by means of a
solvent free thermo-stable adhesive.
All joints on the exterior shall be sealed vapour tight with butyl mastic. A minimum
practical number of joints shall be used. Joints between panels shall be made using
aluminium "H" section on both sides of the panel and 75mm wide x 5mm thick hard
board spline down the middle and full length of the panel.
The gaps between the building walls and the room’s insulated walls shall be filled with
insect and vermin proofed impregnated fibre glass wool and sealed with trimming angle
fabricated from the panel skin material.
The ceiling panels shall be reinforced where necessary to support the forced draft
evaporator. Panel thickness shall be 150 mm for Cold Rooms.
(b) Floors

The room floor shall be insulated as part of the work of this contract provided with a
concrete wearing slab by others.
The structural concrete floor shall be properly primed and vapour sealed with vapour
barrier.
A further 0.25 thick polythene sheet vapour barrier shall be installed. Joints shall be
lapped and taped. An approved adhesive shall be used to fix the sheeting and seal the
joints.
Following the installation of the vapour barrier, the expanded polystyrene insulation
boards shall be laid.
A further 0.25mm thick polythene sheet vapour barrier shall be installed on top of the
insulation, lapped but unsealed at the joints.
Floor surface shall be either: metal deck sheeting; or reinforced concrete acid etched or
mechanically abraded to eliminate surface irregularities with 1:100 falls to floor waste or
doorway.
Aluminium cover strips shall be secured to the base of the walls with a bead of silicone
rubber. Door threshold fitting shall be installed as detailed.
(c) Coving

All wall and ceiling and wall to wall corners shall be fitted with aluminium coving mitred
at the corners and fully sealed with butyl mastic.

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(d) Doors

All doors shall construct as standard detail. Doors shall be insulated with polystyrene
with fibreglass or stainless steel trims and fitted with timber inserts for fixing of hinges
and door handles, etc. As required.
Where timber components are used they shall be fully termite proof.
The door gasket shall be of hollow core type bonded to the door with an approved
adhesive. A neoprene scraper gasket with a stainless steel strip shall be provided at
the bottom of the door.
Hinges and latches shall be chrome plated, lockable type. All doors shall be provided
with an internal safety release mechanism. Hinges shall be rising butt self closing type.
Viewing windows shall be double glazed with sealed cavity.
(e) Wall and Ceiling Penetrations

All wall and ceiling penetrations of rooms shall be closed by vapour sealing.
Where piping or conduits penetrate any part of the Cold Room, P.V.C. sleeves shall be
installed. The sleeves shall be bonded to the insulation panel and the annulus between
the sleeve and pipe packed with mastic.
Electrical penetrations shall be made in a similar manner to the pipe penetrations.

3.10.3 Refrigeration Plant for Cold Rooms and Freezer Rooms

3.10.3.1 General
Condensing units and forced draft evaporators shall be provided as part of the works.
The Cold Room system shall be fully tube up, charged and commissioned.
Condensing unit support stands and evaporator support steel work shall be provided.
The proposed refrigeration capacity and saturated suction temperature to meet
specified room temperature shall be submitted for approval prior to commencing work.

3.10.3.2 Condensing Units

Fully hermetic/semi hermetic compressors with CFC/HCFC free refrigerant.
Condensing units comprising unit base, condenser, receiver, compressor and electric
motor.

Equipment selection shall be made within the manufacturers recommended speed

range for the compressor.

Only equipment with a fully supported spare parts facility in OMAN shall be used.

Refrigerant receivers, where specified, shall be of sufficient capacity to hold the

system charge at 80% full and be fitted with relief valve.

Safety guards shall be fitted to all items of equipment which may cause damage or
injury to personnel or to the building and other equipment.

Ensure that all the equipment offered can be satisfactorily accommodated and served
in the positions allocated.

Condensing units shall be of the air cooled type complete with compressor, motor,
condensing coil, condenser fan and motor, liquid receiver and all ancillary fittings,
controls, etc.

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Compressors shall be fitted with suction and discharge shut-off valves. Condenser
coils shall have copper tubes and aluminium fins.

Condenser fans shall be of the propeller type and shall be arranged to draw air
through the coil.

A solid filter drier together with site glass moisture indicator shall be installed in the
liquid line adjacent to each liquid receiver. Oil traps shall be fitted.

3.10.3.3 Forced Draft Evaporators:

The unit cabinet shall be constructed of heavy gauge hammered aluminium with the
fan and motor assembly rigidly fixed to the cabinet with stainless steel fasteners.

Forced draft evaporators shall be supported on cadmium plated rods and galvanised
angles as required.

The vapour barrier of the Cold Room shall be maintained by sealing to the bolts at the
point of penetration.

Each forced draft evaporator shall incorporate housing, drip tray, cooling coil, fan,
motor, thermal expansion (TX) valve, solenoid valve and liquid and suction line shut off
valves.

Drip tray drains shall be trapped and the run to the nearest drain in 25mm diameter
copper or PVC piping.

Coils shall be staggered type ripple aluminium plate fin with seamless copper tubing.
The unit TX valve shall be accessible.

3.10.3.4 Refrigerant and Oil

The Contractor shall provide the initial charges of appropriate recommended
refrigerant oil and shall also supply and charge it to the system at his own expense
including additional refrigerant during the maintenance period should leakage of
refrigerant occur due to defective parts, materials or workmanship.

3.10.3.5 Controls
The room temperature is to be controlled from a digital type thermostat mounted
adjacent to the Cold Room door. The thermostat shall have an adjustable set point
from and an adjustable differential as specified and continuously displaying the room
temperature.

Room shall be fitted with an additional alarm sensor set 3°C (adjustable) above set
point. The signal from the sensor shall be relayed to the BMCS system.

Room temperatures shall be controlled by operation of a liquid line solenoid valve to

isolate flow to the TX valve. The unit shall cycle off/on from the LP switch.

Unit safety controls shall include refrigerant HP and LP cut-out switches and oil safety
switches where pressurised lubrication systems are fitted to compressors.

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Cold Room controller shall be programmable and shall provide:

 Digital temperature display.

 Defrost control via time and manual control for Freezer Rooms.
 Anti-short cycle control.
 Temperature alarm logging, and defrost logging where appropriate.
 Door switches shall be provided to interlock with the controller to de energise
evaporation fans and close solenoid valves when Cool Room doors are open.

3.10.4 Refrigeration Electrical Work

Electrical work shall be in accordance with electrical division specification.

The electrical work associated with the refrigeration plant comprises essentially:

a) All power and control wiring between the condensing units, switchboards,
thermostats, solenoid valve, safety controls etc.

b) Electrical testing and commissioning of all electrical equipment.

c) Provision of a remote alarm fault signal to the BMCS system.

d) Cold Room shall have fluorescent fitting (rated at -7° Centigrade) or equivalent
Standard fitting to Company approval. The light fitting shall have a Capacitor to0.9
P.F., Low Loss Ballast, Fused terminal, Electronic Pulse Starter and a 4000°K
rendering index Ra84 Tri phosphor tube with a minimum life of 13,000 hrs. Light
switches shall be 15A (IP56). Socket outlets to IP56 minimum standard RCD
(residual current device) protected.

e) Light switches shall be mounted adjacent to the door inside the room - not
switched from outside the room - with a neon indicating light outside the room
adjacent to the door.

3.11 Water Cooler

Self-Contained Drinking Water Cooler with Non CFC/HCFC Refrigerant, Energy
Efficient Compressor.

a) The water Coolers shall be suitable for operation on 230 V +/-10 %, 50 Hz, single
phase A.C. supply.

b) Tank shall be fabricated from stainless steel Sheet of 0.8mm minimum thickness
as per AISI 304 and shall be made by electrically seam welded lap joints sheet with
PUF insulation. However tank fabricated by double seam jointing is also acceptable
if the same is reinforced and sealed by lead-free solder material. Use of lead
soldering material for sealing the joints of water tank is not permitted. Water tank
cover and lid bottom shall be made of 1.25mm aluminium sheet duly anodized/epoxy
painted/high impact polystyrene (HIP) of 1.5mm thickness. A drain valve at the
bottom of the storage tank to be provided to draw out water while cleaning.

c) The cabinet, drain pan and front panel below the water outlets of the type water
coolers shall be made of stainless steel sheet of 1.0mm. The bottom pedestal shall
be made of 2.65mm minimum thick stainless steel sheet. Pedestal shall have a
minimum ground clearance of 100mm for ease of cleaning. Pedestal shall be strong
enough to withstand weight with storage tank full and shall be reinforced to prevent a

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skewing. The body shall be held securely with the pedestal with stainless steel nuts
and bolts. The drain size should be 25mm or above. In case water outlets are
provided on three sides then all the three lower panels should be made of aluminium
sheet or stainless steel sheet.

d) The mild steel components used in the manufacture of the cabinet shall be
individually degreased, pickled, scrubbed and rinsed to remove grease, rust, scale or
/any other foreign elements. Immediately after pickling the M.S. parts shall be given
phosphate treatment. The components along with the front panels shall then be
given a primer coat with a finish coat of stove enamel paint. The finish shall be
smooth and uniform with hard tough film of the enamel adhering to the surface. The
finish shall be free from all the visible defects and shall not chip when tapped lightly
with a dull pointed instrument. Alternative method of corrosion protection like plastic
powder coating, electrostatic painting shall be permitted.

e) Refrigeration coils to be fully soldered to the outside of the tank for good thermal
contact and not merely tack welded.

f) There shall not be any gap between water tank cover (mask) and water tank to
prevent rodent/inspect/dust entry.

g) Condenser fan motor shall be capacitor start and capacitor run (CSR) or
permanently split capacitor (PSC) or alternatively permanently lubricated motor may
be provided.

h) Water tank overflow should be adequately covered with strainer such as wire
mesh etc. to avoid rodent/insect/dust entry.

i) The power factor of water cooler shall not be less than 0.85 at capacity rating test
conditions.

j) The position of the thermostat shall be adjustable through a rotary switch mounted
on the front or side panels. Minimum and maximum of the thermostat setting shall be
from 10 deg C and 25°C which shall be marked.

k) During inspection performance of thermostat shall also be checked at minimum

and maximum positions.

3.11.1 Bottle Water Type Water Cooler Units

Hot and Cold Units: These units dispense both hot and cold water. These units have
both an electric resistance heater and a refrigeration cycle.

Reservoir: To be constructed of Type 304 Stainless Steel. External copper

refrigerant coil. Reservoir insulation is to be removable and made of moulded,
expanded bead polystyrene.

Refrigeration unit: Convection cooled condenser. Internally spring- mounted,

hermetically sealed compressor with automatic overload protector. No lubrication
required. Refrigerant is controlled by accurately calibrated capillary tube.

Thermostat: Temperature is controlled by adjustable thermostat, with “off " position,

easily accessible on rear of cabinet.

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Hot Tank: Unit shall contain a 500 watt heating element externally bonded. Entire
assembly can be removed without breaking soldered connections. Tank to be
constructed of red brass or type 304 stainless steel.
Hot Water Thermostat: Water Temperature is controlled to 180 degrees by
automatic thermostat.

Hot Water Capacity: Shall contain 45 six ounce cups of hot water per hour, with a 1-
1/2 quart storage tank.

Faucets: Self closing type. Made of durable polypropylene.

Drip Receptor: Made of rugged moulded polystyrene. Must be easily removable for
cleaning.

Sides: To be constructed of 20 gauge steel panels with standard finish of catholically

electro-coated acrylic enamel in colour.
Top: Made from high impact ABS colour moulded all the way through Standard finish
colour.

Front: Upper part made of high impact polystyrene with colour. Lower part in Walnut
Wood Grain vinyl on steel or be finished in Mocha Tan or Beige colour.

* Notes:
* All components in the above water cooler units are to be lead free.
* All models must be U.L. approved.
* Water cooler unit specifications listed above may vary depending upon make and
model of unit being offered and should not be construed as the only units that may
be accepted within this package. The Company reserves the right to accept and/or
reject units upon inspection.

3.12 Ice Maker

Ice maker shall have the standard features as following:

Air cooled/water cool, Half/full dice cubes , production minimum as per schedule at
specified ambient temperature, self diagnostic system, stainless steel Exterior, self
cleaning, hinged front panel, no plastic on outside, stainless steel front, top and side
with steel louvers, tamper proof screws, bits included. CFC free refrigerant must
include water filter system, UL listed.
This specification covers automatic, electric motor-driven self-contained,
mechanically refrigerated, ice making machines.

Standard product; the ice making machine delivered under this document shall be
the contractor's standard commercial product except for changes necessary to meet
the document requirements. All like items furnished on any one contract, including
parts and subassemblies thereof, shall be new and interchangeable.

Design: The ice making shall be a complete self-contained unit composed of an ice-
making section and a storage bin. The machine shall have a means of a harvesting
and storing ice, water circulating system, motor or motor drives, and all necessary
piping, wiring, control and safety devices, with automatic control of ice level in
storage bin. All parts shall be located to permit repair or replacement. All operating
parts subject to vibration shall be mounted on vibration elimination units to prevent
the transmission of vibration during normal use. All accessories, including fans,
reduction gears, harvesting equipment, and pumps shall be directly connected.

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When the ice machine is operated, all mechanical and electrical controls and parts
shall function according to design. Minor disassembly of components to accomplish
clearance dimensions is permitted, but this shall not include disassemble of
refrigeration or electrical components.

Controls: Controls shall be designed to include a device to automatically operate the

ice making machine. The controls shall automatically stop the ice making process
when the predetermined level of ice in the storage bin is reached and automatically
restart the ice making process when the amount of ice is reduced below the
predetermined level. Controls shall comply with the operational and electrical
requirements.

Capacity: The ice making machine shall be capable of making and harvesting ice as
per the schedule.
Ice produced shall be cube ice. Cube ice normally refers to a fairly uniform product
that is hard, solid, usually but not necessarily clear, and generally weighs less than 2
ounces per piece, as distinguished from flake, crushed, or fragmented ice. The ice
may be formed by any method and in any shape consistent with the manufacturer's
standard

Performance: The ice making machines shall operate without malfunction or failure
of any component and shall not exceed motor ratings and temperatures when
operated for a minimum of 2 continuous hours.
Codes and standards: The ice making machines shall comply with the applicable
requirements of Underwriters Laboratories Standard No. 563 and ARI 810.

3.13 Refrigerator
General: A device described as a Refrigerator maintains a temperature a few
degrees above the freezing point of water.

Construction: Outer body and doors shall be made of 20 gauge 304 grade stainless
steel sheets. Door shall be with latch arrangements and magnetic gasket duly fitted
with heavy duty stainless steel hinges. Stainless steel legs with nylon adjustable
bushes are provided at the bottom.

The refrigerator shall be equipped with separate freezer and refrigerator

compartment with separate access door.
The compressor compartment at the top/bottom shall be provided with stainless
steel finned. It has to operate on single phase, 230 volts, 50 Hz of electric supply.
Refrigerator cabinet will have door operated light connection.

A separate stainless steel sliding tray shall be provided at the bottom of the cabinet
to collect the defrost water. Vendor shall give 24 months warranty for the Entire unit
and compressor for 5 years.

Temperature Range: Refrigerator 1.11°C to 4.4 °C (30° F to 40° F), Freezer -17 °C
to -12 °C (0° F to 10° F)

Evaporator: The cooling system should be indirect fan cooling type. Frost free coil
with protective film with auto defrost cycle.

Freezer: Wrap around body with 3/8” copper coils of bright annealed surface from
inside, is soldered to the outer surface of the inner tank.

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3.13.1 Deep Freezer

Vertical /Horizontal Deep freezer shall be with the following technical specification.

Body and door shall be made of 20 gauge 304 grade stainless steel sheets. High density
PUF insulation. Deep freezer should have Temperature range of -20°C to -30°C.

Temperature, voltage input indicators should be in-built with alarm system and digital
displays.

Microprocessor based control system with audio-visual alarm for temperature deviation.
Refrigerant shall be HFC (CFC & HCFC Free).

3.14 Testing & Commissioning

3.14.1 General
The general requirements for testing & commissioning and handover are given in
‘Section-1: General Requirements’. This chapter includes:
- Commissioning Method Statement
- Commissioning Programme
- Test Equipment
- System Demonstration
- Pipe work Leakage Testing.
- Documentation
- Maintenance Tools
- Spare Parts
- As Built Drawings
- Operation & Maintenance Manuals
- Exceptions List Refer: STD-2-1702-A02 appendix C of section 2 page
16
- Handover Report Refer: STD-2-1702-A03 A02 appendix C of section 2
page 16

The commissioning of a chilled water air-conditioning system should normally be carried out
in the following sequence.
- Chilled water flush, test and dose.
(Since the pipe work circuit is usually available first).
- Chilled water pump start up. Pressurisation unit start up.
- Chilled water initial balance.
- Airside integrity check and fan start up.
- Air initial balance.
- Water chiller start up
- Control function check.
- Waterside and airside final balance.
- Control system calibration.
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The standard Air conditioning Test Sheets included in Appendix B of this document,
or equal and approved by the Company shall be used to record measurements and
demonstrations.

3.14.2 Test Instruments

Unless otherwise specified by the Principal, the Supplier of the HVAC system shall
provide all test equipment required to commission and maintain the whole HVAC
system. Test equipment may include gauge manometers, anemometers, Pitot tubes,
hygrometers, thermometers, tachometers, sound analysers, vibration meters,
recorders (for tuning control loops), etc.
The Contractor/Supplier shall submit a proposed list of test equipment to the
Company and as a minimum shall include, but not be limited to:
- Anemometer for air velocity.
- Clamp Meter for current and voltage.
- dBA Meter for noise level.
- Flow meter for chilled water flow at metering stations.
- Hygrometer for humidity.
- Manometer for pressure difference.
- Pitot tube for airflow.
- Tachometer for rotational speed.
- Thermometer for temperature.
- Sling Psychomotor for air temperature and relative humidity
- Digital hood flow meter for air velocity.
Note: all the equipment should be digital type.

3.14.3 Testing & Commissioning Procedures

3.14.3.1 Tests and Inspections During Construction
The purpose of these tests is to ensure that all components and systems are in a
satisfactory and safe condition before start up. Preliminary adjustment and setting of
equipment at this stage shall also be carried out at the same time for the coming
functional performance tests.
Before carrying out any test, the contractor shall ensure that the installation complies
with all relevant statutory requirements and regulations. The testing and
commissioning (T & C) works shall also comply with all site safety regulatory
requirements.
3.14.3.2 Functional Performance Tests
The purpose of functional performance tests is to demonstrate that the equipment
installation can meet the functional and performance requirements as specified in the
Specifications. Functional performance test should proceed from the testing of
individual components to the testing of different systems in the installation.
Any performance deficiencies revealed during the functional performance tests must
be evaluated to determine the cause and whether they are part of the contractual
obligations. After completion of the necessary corrective measures, the contractor
shall repeat the tests.
If any test cannot be completed because of circumstances that are beyond the
control of the contractor, it shall be properly documented and reported to the

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Company, who shall then liaise with the relevant parties to resolve the situation. The
contractor shall resume his testing work immediately upon the attainment of a
suitable testing environment.
3.14.3.3 Commissioning and Statutory Inspections

Commissioning is the advancement of an installation from the stage of static

completion to full working conditions and to meet the performance requirements as
specified in the Specification. This will include setting into operation and regulation of
the installation. It is expected that fine-tuning of the commissioned system shall be
done by the contractor to match system performance to the actual needs of the
building more closely.
3.14.3.4 Work Tests

Work tests shall be carried out in accordance with the type normally associated with
the specified item of equipment and to the standards as laid down in the
Specification and the Contract.
3.14.3.5 Weld in Piped Services
The Company reserves the right to inspect at random the welded joints. Should any
of the above welds prove faulty in materials or workmanship, further removal of
welds may be ordered. If any of the welds fail the tests, it is sufficient to conclude
that an operative is not consistent in standard. The Company may order any number
of the operative’s welds to be removed. The contractor shall be responsible for
cutting out and repair of all such welds for inspection.

3.14.4 Chilled Water

3.14.4.1 Leakage Testing of Pipe Works

Before carrying out leakage/pressure test, spotted open-up inspection for joints shall
be required to inspect the internal finishing after brazing to ensure the quality of the
workmanship.
Prior to application of insulation and painting to the welded pipe joints and cleaned
pipe surfaces, all water pipe work shall be hydraulically pressure tested to 1.5 times
the maximum working pressure (24 bar) in the system for not less than 24 hours
suggested, without leakage or loss of pressure. The maximum working pressure
shall be deemed to be the static head plus the total pump head. The minimum test
pressure for water pipe is 10 bars. The safety should be considered as per
Company’s standard.
All sections of pipe work shall be tested during installation of the Works. Pipes shall
not be insulated, covered-in or otherwise made inaccessible, before testing.
Test requirements for each service are given in the relevant Sections of these
Specifications. . A standard pipe work leakage test record pro-forma is given in
Appendix-C in section-2
Test branches and plugs shall be provided as required, whether shown on the
Contract Drawings or not, and shall be sealed off or removed on completion of
testing as required by the Company.
Tests shall be performed correctly, and re-tested after remedial work so that, on
completion of the system, each and every section shall have been satisfactorily
tested. On completion, each system shall be re-tested as a whole.
Test pressures shall be applied upstream of check valves. Sectional tests shall be
carried out before painting, insulation or concealment.
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Instruments shall be excluded from tests, unless otherwise specified. Diaphragm

connections on pressure balance control valves shall be removed during tests.
Relief valves shall be blinded off or gagged but spring settings shall not be adjusted.
Tests shall be recorded and signed by the Contractors senior representative on site,
and so far as possible, witnessed by the Company.
Pipe work Leakage Test Report contained in Section 2.
A complete set of pipe work leakage test reports shall be included as part of the
Operating and Maintenance Manuals.

3.14.4.2 Chemical Dosing

Before treatment, the complete chilled water system shall be flushed to the approval
of the Company and a final leakage test performed. Large bore (minimum 50mm)
flush points, at lowest sections of the system, shall be provided.
The system shall then be dosed with a de-scaling agent and left for a minimum of 24
hours.
The system shall then be drained down, re-flushed, re-filled and dosed with a
corrosion inhibitor and an algae inhibitor.
Table below gives details for treatment. Manufacturers and products may be used,
subject to Company written approval.
Table Chemical Dosing
Treatment Dosage
De scaling 5 litres per 1 m3 of system volume
Anti- 10 litres per 1 m3 of system
corrosion volume
Algae 1 litre per 10 m3 of system volume

The measurements listed on the following document shall be recorded. (See

Appendix-B)
1285-B04 Chemical Dosing Test Sheet page 174 Appendix-B

3.14.4.3 Chilled Water Pumps

The manufacturers shall provide pump curves; specific to each pump, for commissioning and
copies shall form part of the Operation and Maintenance Manual.
The measurements listed on the following document shall be recorded.
1285-B06 Chilled Water Pump Test Sheet page 177 Appendix-B

3.14.4.4 Pressurisation Units

Chilled water pressurisation unit filling and commissioning procedures shall be in accordance
with the Manufacturer's Instructions.

3.14.4.5 Initial Chilled Water Balance

The chilled water balance shall be carried out with;

- 'Normally Open' manual valves fully open.

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- Strainer baskets clean.

- Air vents functioning correctly and air bled from the system.
The initial chilled water balance should be based on design flow rates measured at
metering stations and may be carried out before water chiller start up.

Method statement shall be provided for chilled water balancing.

a. Balance system on a day which imposes a reasonable percentage of loads on the

systems.
b. Whenever possible, coil balancing shall be done with inlet water and air
temperatures set at design values.
c. Check the cleanliness of system water. It should be certified by the water
laboratory.
d. Position all control valves and manual valves for full flow through coils, etc., during
tests.
e. Use only calibrated test gauges for tests; pressure gauges installed with system
shall not be used.
f. Coordinate setting of controls to maintain coil water inlet design temperatures and
for full flow through coils during adjustment.
Adjusting the balancing of water systems shall include, but not be limited to, the
following:
a. Permanently mark settings of valves and other adjustment devices allowing
settings to be restored. Set and lock memory stops.
b. After adjustment, take measurements to verify balance has not been disrupted or
that such disruption has been rectified.
c. Leave systems in proper working order, closing access doors, closing doors to
electrical switch boxes, and restoring thermostats to specified settings.
d. Adjust water systems to provide required or design quantities.
e. Use calibrated Venturi tubes, orifices, circuit balancing valves, control valve
performance, or other metered fittings and pressure gauges to determine flow rates
for system balance. Where flow metering devices are not installed, base flow
balance on temperature difference across various heat transfer elements in the
system.
f. Adjust systems to provide specified pressure drops and flows through heat transfer
elements prior to thermal testing. Perform balancing by measurement of temperature
differential in conjunction with air balancing.
g. Effect system balance with automatic control valves fully open to heat transfer
elements.
h. Effect adjustment of water distribution systems by means of balancing cocks,
valves, and fittings. Do not use service or shutoff valves for balancing, unless
indexed for balance point.
The measurements listed on the following document shall be recorded.

Appendix-B 1285-B03 Chilled Water Balance Test Sheet

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3.14.4.6 Water Chillers

Commissioning of chiller units shall be carried out by properly certificated technicians
and shall include, but not be limited to:
- Start up checks according to Manufacturer's recommendations.
- Running tests according to Manufacturer's recommendations.
A full load test performed during summer months. If Substantial Completion takes
place outside this period, the full load test shall be performed during the Defects
Liability Period.
- Training and instruction of Company operatives.
The measurements listed on the following documents shall be recorded.
- Manufacturers Start-up Checklist
- Manufacturers Running Test Report
- Appendix-B 1285-B05 Water Chiller Full Load Test Sheet

3.14.5 Air Systems

The following ductwork system shall be tested for leakage rate in accordance with
ASHRA SMACNA requirements or DW 143 (Where applicable).
The duct work system prior to application of insulation and painting, all installed
ductwork, including exhaust, smoke extraction, air-conditioning, ventilation, etc., shall
be tested. The method of air leakage test shall follow the HVCA standard DW/series
or the Duct Construction Standards” issued by the SMACNA. Air ducts shall be
leakage tested and any defects shall be rectified before applying insulation and
commissioning.
The joints on ductwork shall be tested by using chemical 'white' smoke generators or
lighting test. All openings such as fan outlets, grilles, access panels, test holes, etc.
shall be sealed before the smoke is introduced. If smoke leaks from any joint, that
joint shall be made good. The smoke test shall be repeated until all joints are tested
and to be properly sealed.

3.14.5.1 Air Systems Generally

Before fan start-up:
- Ductwork shall be thoroughly clean and free from obstructions.
- Dampers shall be open.
- Mechanical and electrical checks for the proper and safe operation of
equipment shall have been completed.
Before test measurements are taken:
- Ductwork shall be blown through, before fixing grilles and diffusers, to clear
dust.
- Filters shall be clean.
- Belt tensions shall be checked and adjusted as necessary.
- Drainage traps shall have water seals.
- Joints, covers, test holes, builders work penetrations etc. shall be sealed.

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3.14.5.2 Air Initial Balance

The initial air balance, based on design flow rates, may be carried out before water
chiller start up. Systems may be balanced by setting the correct proportional airflows
at junctions back to the fan and the design flow rates achieved by adjustment of the
main damper. Main airflow shall be measured by Pitot tube traverse or equal and
approved by the Company.
Method statement shall be provided for air balancing.
a. Measure air volumes by means of the duct traverse method.
b. Adjust balancing dampers for required branch duct air quantities.
c. Total air delivery in duct system shall be obtained by adjustment of volume
dampers in applicable systems. Driver motor of fan shall not be loaded over
corrected full load amperage rating of motor.
Adjusting and balancing of air systems shall include, but not be limited to, the
following:
a. Adjust air handling systems to ±10 per cent for supply systems and ±10 per cent
for return and exhaust systems from airflows indicated.
b. Permanently mark settings of dampers and other adjustment devices allowing
settings to be restored. Set and lock memory stops.
c. After adjustment, take measurements to verify balance has not been disrupted or
that such disruption has been rectified.
d. Leave systems in proper working order, replacing belt guards, closing access
doors, closing doors to electrical switch boxes, and restoring thermostats to specified
settings.
e. At final inspection, recheck random selections of data recorded in report. Recheck
points or areas as selected and witnessed by the Company.
f. Check and adjust systems approximately six months after provisional acceptance
and submit report. The Contractor shall be responsible to perform any required
corrections to the systems installation, and shall retest.
g. Adjust air handling and distribution systems to provide required or design supply,
return, and exhaust air quantities at site altitude.
h. Make air quantity measurements in ducts by Pitot tube traverse of entire cross
sectional area of duct.
i. Measure air quantities at air inlets and outlets.
j. Adjust distribution system to obtain uniform space temperatures free from
objectionable drafts and noise.
k. Use volume control devices to regulate air quantities only to extent that
adjustments do not create objectionable air motion or sound levels. Effect volume
control by duct internal devices such as dampers and splitters.
l. Vary total system air quantities to design values by adjustment of fan speeds, but
in no way exceed the manufacturer’s rating. The Subcontractor shall provide drive
changes required. Vary branch air quantities by damper regulations. Set fan volume
control.
m. Provide system schematic with required and actual air quantities recorded at
each outlet or inlet.
n. Measure static air pressure conditions on air supply units, including filter and coil
pressure drops, and total pressure across the fan. Make allowances for 50 percent
loading of filters.

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o. Adjust outside air automatic dampers, outside air, return air, and exhaust dampers
for design conditions.
p. Measure temperature conditions across outside air, return air, and exhaust
dampers to check leakage.
q. Where modulating dampers are provided, take measurements and balance at
extreme conditions. Balance variable volume systems at maximum airflow rate, full
cooling, and at minimum airflow rate, full heating.
r. Measure building static pressure and adjust supply, return, and exhaust air
systems to provide required relationship between each to maintain approximately
30pa.Positive static pressure near the building entries.
s. Completely fill out exhaust data and summary stickers on exhaust drops.
t. Take voltage and amperage readings on fan motors.
The measurements listed on the following documents shall be recorded.
- 1285-B01 Air Balance Test Sheet page 171 Appendix-B
- 1285-B07 Centrifugal Fan Test Sheet page 178 Appendix-B

3.14.6 Control Systems

3.14.6.1 Preliminary Checks

Before starting to set up a controls system the following requirements shall be
satisfied:
- All electrical supplies shall be isolated.
- All control components shall be correctly selected and installed.
- All safety devices, including interlocks and cut-outs, shall operate effectively.
- All sensing elements shall be located so as to give good representation of
the controlled variable.

3.14.6.2 Control Function Check

Each component group, e.g. temperature sensor with directly associated control
valve, shall be separately functionally tested. Each function check shall be carried
out at least twice.
Function checks shall include, but not be limited to, verification that:
- The set points of all controllers are within design tolerance with the minimum
dead zone consistent with stable control.
- Actuators have the correct movement initiated by controllers.
- Interlocking and overriding devices ensure that the overall sequence of
control is achieved.
- Equipment protection devices operate satisfactorily.
- Devices activated by fire alarm operate satisfactorily.
- Safety is not jeopardised in the event of the interruption the electrical supply.

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3.14.7 Final Balance & Calibration

3.14.7.1 Waterside & Airside Final Balance

With the complete system functional and running, the waterside and airside balance
shall be fine-tuned to take account of design temperature differences across
equipment and to achieve the specified room conditions.
When finally balanced, the adjusted position of each balancing valve and damper
shall be permanently marked.

3.14.7.2 Control System Calibration

With the complete system functional and running and the waterside and airside
finally balanced, controllers shall be fine-tuned to ensure that set points and control
tolerances are correct and meet the specified requirements.

3.14.7.3 Noise Levels

Noise measurements of the A-weighted sound pressure level (dBA) shall be taken:
- In at least 3 locations relevant to occupation.
- Under normal operating conditions.
- At least 1 m away from any reflecting plane or opening of the air-conditioning
system, and at least 1.5 m away from any window
- For at least 10 seconds.
In cases where anyone measurement indicates possible non-conformance with
specified noise criteria, then octave band spectra measurements shall be taken to
establish the noise rating (NR) as listed on the following document.
- 1285-B13 Sound Level Test Sheet page 185 Appendix-B

3.15 Supervision

3.15.1 Contractor’s Supervisor

A qualified supervisor minimum 10 years’ experience fluently conversant in the
English language and experienced in the air conditioning work shall be employed by
the Contractor on the Worksite and shall directly supervise all the work.

3.15.2 Company Inspection

The Contractors shall give at least one week notice, to the Company Site
Representative, so that he may inspect the work. After inspection the CSR will inform
the contractor about necessary improvement or allow the contractor to continue with
the next sequence of the work. Such permission will not relief the contractor in any
way from his responsibilities as to carry out the works in accordance with the
contract and specifications.

3.15.3 Handover Documentation

The final documentation shall at least include:
- Engineering flow schemes ('as built');
- Design criteria and data summary;
- Layout and location drawings for each plant building;
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- Calculation sheets for ventilation rates, pressurisation, normal and abnormal cooling,
heating load etc.
- Control and alarm schemes;
- Electrical power supply and distribution drawings;
- Hardware/software related drawings for control, alarm and shutdown functions;
- Start-up, shutdown, trouble shooting and regular maintenance procedures;
- operating manuals;
- Technical data books and spare parts listings;
- Certification or declaration that all electrical equipment is suitable for use in
hazardous areas (where applicable).
The Contractor/Manufacturer/Supplier shall submit a listing of hand-over documents to the
Company.

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Section 4: Electrical Specification for Heating,

Ventilation & Air-Conditioning

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4.1 Abbreviations

AC Alternating Current

ACB Air Circuit Breaker

Amp Ampere

AWA Aluminum Wire Armoured

CBCT Core Balance Current Transformer

Cu Copper

DC Direct Current

DDC Direct Digital Control

DEP Design Engineering Practice (Shell)

FCS Field Bus Control System

FGS Fire and gas system

Hz Hertz

IP Ingress Protection

IPF Instrumented Protective Function

kA Kilo-Ampere

kW Kilo-Watt

LBS Load Break Switch

LV Low Voltage

LSIG Long-time + Short-time + Instantaneous + Equipment

Ground-fault Protection

MCC Motor Control Centre

MCCB Moulded Case Circuit Breaker

PVC Polyvinyl chloride

RCU Remote Control Unit

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SCADA Supervisory Control and Data Acquisition

SFU Switch Fuse unit

SP PDO Specification

SWA Steel Wire Armoured

UPS Un-interrupted Power Supply

V Voltage

VSD Variable Speed Drive System

XLPE Cross-linked polyethylene

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4.2 Electrical Requirements

4.2.1 HVAC equipment for building shall be fed from the HVAC MCC as per PDO
electrical specification. Company shall provide redundant incoming power
supply to the HVAC MCC. From HVAC MCC to all electrical downstream
system required for successful operation of the HVAC system shall be in
scope of HVAC Contractor / Vendor.

4.2.2 Single point 240V AC, 50 Hz power supply (UPS supply preferred if
available) shall be supplied to HVAC DDC (Direct Digital Control) panel in
addition to one normal 240V 50 Hz power supply required for the utilities of
DDC like heaters, fans, panel lights and sockets as applicable.

4.2.3 The power and control circuits shall be physically segregated by housing
them in separate compartments.

4.2.4 Hazardous area classification shall be ‘safe’ and degree of protection shall
be IP55 and IP41 for all outdoor and indoor electrical equipments
respectively. However, for battery room, the exhaust fans shall be suitable
for Zone 1, Gas Group IIC, T4.

4.2.5 A plant earthing system shall be provided by others. All electrical and
mechanical equipments including condensing unit and air handling unit shall
be provided with two diagonally opposite earthing points (to be provided by
HVAC Contractor /Vendor) on the unit. These units shall be bonded to the
plant earthing system by HVAC Contractor /Vendor using Yellow / Green
PVC cable size as mentioned in Clause 3.2 (Appendix-2) of SP-1109.

4.2.6 The condensing units along with all electrical, instrumentation shall be
suitable for outdoor installation without sunshade. All HVAC condensing unit,
Heaters for AHU, AHU’s, Chillers and exhaust fans working / stand by
selection shall be controlled automatically by DDC system.

4.2.7 All the electrical equipments viz. motors and instrumentation located
outdoors shall be suitable for 82°C black bulb temperature. All electrical
equipments that are not in the air conditioned environment like substation
building shall be designed for an ambient temperature of 55°C. All electrical
equipments located in shade shall be suitable for 55°C shade temperature. It
is to be noted that shade effect shall not be considered for some of the
motors viz. fresh air fan motor, motors of volume control dampers. Also
Vendor to check and confirm that motors in condensing units and air
handling units are in sheet metal enclosure of respective units and hence
can be treated as “under shade”. Such motors shall be suitable for 55°C.

4.2.8 Final paint shade of all electrical equipment shall be RAL7035.

4.2.9 Also refer SP-1285 for additional electrical details.

4.2.10 Make of all electrical equipment shall be as per Company approved Vendor
list (AVME) except those motors not forming part of AHU.

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4.3 415V HVAC MCC

4.3.1 HVAC equipment for the building shall be fed from dedicated 415V LV HVAC
MCC as per PDO electrical specification.

4.3.2 The 415V LV HVAC MCC shall be in full compliance with requirements of
SP-1121, SP-1103, DEP 33.67.01.31-Gen., DEP 33.64.10.10-Gen. and
standard drawings referred in these specifications like S67.004 & S67.019.

4.3.3 The 415 V Circuit breakers / contactors shall be Air Insulated Type.

4.3.4 The 415 V LV HVAC MCC shall be as per the technical requirements
specified in data sheet and site climatic conditions referred in this document.

4.3.5 The 415V LV HVAC MCC shall be metal enclosed, metal clad with Form-4
type construction. All the incoming and outgoing feeders shall be of draw out
type (Except for the group single phase outgoing feeders). The busbar cover
shall be with bolted enclosure (cover); however cable alley cover shall be
with hinged enclosure (cover).

4.3.6 Final paint shade for HVAC MCC & control panel shall be RAL 7035.

4.3.7 The 415V LV HVAC MCC shall have two incomers and one bus coupler
without changeover arrangement, all with load break switch (LBS) with 2 out
of 3 mechanical interlock arrangement. Each LBS shall be rated for the
100% load requirement of HVAC Equipment.

4.3.8 The 415 V LV HVAC MCC shall be Single front type and shall have only front
access as the 415 LV HVAC MCC shall be installed flushed to the wall from
rear side.

4.3.9 Where the rating of the LV circuit (excluding motor feeders) is 100A and
above, in order to ensure proper protection coordination, current limiting type
MCCB with LSIG protection release shall be provided. Protection
coordination with upstream MCCB / ACB and downstream MCCB / fuse
shall be ensured. Earth fault protection is required for feeder rating 100 Amp
and above.

4.3.10 Feeder for Motor rated 30kW and above shall be provided with Core
Balance Current Transformer (CBCT) and earth fault relay.

4.3.11 All motor starter modules in MCC shall have Switch fuse unit (SFU) and
Remote Control Unit (RCU) shall be provided near to the motors for local
operation and maintenance. In addition motors rated 75kW and above shall
be provided with space heater / anti condensation heater. Safety switch shall
be provided for space heaters close to the motor.

4.3.12 Feeder for Motor rated up to and including 2.2kW shall have in line RCU
with direct reading ammeter arrangement.

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4.3.13 For motor feeders; rating of contactor, overload relay, fuse, fuse base &
components shall be selected by Vendor to conform to Type-2 coordination
as specified in IEC 60947-4-1.

4.3.14 All motor feeders shall have SFU, contactor and thermal overload relay.

4.3.15 Motor starter as well as power feeder module in HVAC MCC shall be
provided with pad lock facility.

4.3.16 For all Power feeders, LBS with pad lock facilities shall be provided near the
package equipment for local Isolation.

4.3.17 The rating of any fuse protected LV circuit which derives power supply from
the 415V switchboard should not exceed 25% of the rating of the
transformer incomer to the switchboard or 100A, whichever is lower.
Similarly, the rating of any fuse-protected LV-circuit which derives power
supply from a 415V DB should not exceed 50% of the rating of the fuse
protected 415V incomers to the distribution board.

4.3.18 All indicating lamps, metering and control switches shall be in line with PDO
standards.

4.3.19 Electrical heaters and Thyristor Control Panel shall be in accordance to DEP
33.68.30.33-Gen as applicable.

4.3.20 AC electrical Variable Speed Drive system shall be in accordance to DEP

33.66.05.33-Gen.

4.3.21 The 415V LV HVAC MCC shall be designed so as to facilitate extension on

both sides.

4.3.22 20% spare terminals shall be provided in the terminal block.

4.3.23 Cable entries to the 415V LV HVAC MCC shall be from bottom. 415V LV
HVAC MCC shall be provided with un-drilled gland plate of adequate size,
for fixing cable gland. 415V LV HVAC MCC shall be provided with cable
glands, lugs etc.

4.3.24 The draw out portion of all the modules of a particular type and rating shall
be completely identical and interchangeable.

4.3.25 The short circuit rating of the 415V HVAC MCC shall be min 50kA for 1 sec
or as per project specific requirement whichever is higher.

4.3.26 Power/control cables shall be supplied by HVAC Contractor / Vendor except

incoming power supply cable to HVAC MCC and 240V AC supply cable to
DDC panel. Power/control cables shall be Cu/XLPE/SWA/PVC type. Single
core cables shall be Cu/XLPE/AWA/PVC. Sizing of cables shall be done in
such a way that steady state and dynamic voltage drops shall not exceed
the limits specified DEP 33.64.10.10-Gen.

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4.3.27 Power supply to Exhaust fans in Toilets /Bathrooms / Pantry shall not be
powered from HVAC panel. Same shall be powered from Lighting and Small
Power Distribution board. However, exhaust fans in Battery room, Mess &
Kitchen shall be powered and controlled from HVAC panel.

4.3.28 All Air Heaters wherever required shall be provided with local safety switch
(for single phase heater) or Load Break Switch (for three phase heater) pad
lockable type in off position for Isolation.

4.3.29 Local / Remote switch shall be provided in DDC panel. No Local / Remote
switch shall be provided in Motor modules. In local mode, it shall be possible
to operate and maintain any motor from local RCU and Load Break Switch
as the case may be.

4.3.30 Corresponding to each AHU, dampers shall have on/off switches to enable
local maintenance of associated motors.

4.3.31 Load Break Switch / RCU for local Isolation (pad lockable type in off
position) near the unit shall be provided for following HVAC systems:

4.3.32 Window AC

4.3.33 Split AC - Local Isolation required for both Indoor unit as well as Outdoor unit

4.3.34 VRV Units ( Variable Refrigerant Volume) - Local Isolation required for both
Indoor unit as well as Outdoor unit

4.3.35 Package AC Units - Local Isolation required near the unit

4.3.36 Condensing Unit and AHU - Local Isolation required for condensing unit.
Remote control unit (RCU) is required for each AHU motors. If motors are
provided with space heater (>= 75kW) then safety switch near motor is also
required for local Isolation.

4.3.37 AHU - Remote control unit (RCU) is required for each AHU motors. If motors
are provided with space heater (>= 75kW) then safety switch near motor is
also required for local Isolation.

4.3.38 Chilled Water System - Local Isolation required near the unit.

4.4 Motors

4.4.1 All AHU motors shall be in line with SP-1119, SP-1103, DEP 33.66.05.31-
Gen and DEP-33.64.10.10-Gen and shall be procured from PDO AVME list.
All other motors shall comply with IEC 60034-1, IEC 60034-5, IEC 60034-12
and IEC 60034-14 and 60034-18.

4.4.2 The cage induction type motors forming part of an AC Variable Speed Drive
System (VSDS) shall comply with DEP 33.66.05.33-Gen, as applicable.

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4.4.3 All motors rated 75kW and above shall be designed complete with anti-
condensation space heaters (240V, single phase, 50Hz) for use when
motors are out of service. The anti-condensation space heaters shall be
engaged automatically when the motors are stopped and de-energized.
Safety switch shall be provided near to motor for anti-condensation space
heater. The anti-condensation heater terminal shall be provided in separate
terminal box on motor.

4.4.4 The cooling system for all the motors shall be provided in accordance to
IEC.

4.4.5 Ingress protection for motor enclosure & terminal boxes shall be IP 55.

4.4.6 All insulation materials shall be Class F, as defined in IEC 60034-18. The
rating of the machine offered by the Manufacturer shall be based on a Class
B temperature rise for all parts of the machine windings.

4.4.7 The sound pressure level of the loaded machine shall not exceed 77 dB(A)
in the work area, measured in accordance with ISO 1680.

4.4.8 Minimum efficiency at full load of LV motors shall comply with IE2 (High
efficiency) of IEC60034-30

4.4.9 Final paint shade for motor shall be RAL 7035.

4.4.10 Motor body shall be provided with two (2) diagonally opposite earthing
bosses. The motor terminal box shall have separate earthing arrangement.

4.4.11 All motors shall be rated less than 160 KW and voltage levels shall be in line
with SP-1103 Appendix 2.

4.5 Exhaust Fan

4.5.1 Wall mounted exhaust fans, 2 Nos (1 working + 1 stand by) for each battery
room shall be provided. Each fan shall be provided with electric motor.

4.5.2 Battery room fans shall be explosion proof and shall be provided with
motors suitable for Zone 1, T4 rating, Gas Group IIC, T4, high efficiency,
totally enclosed with Class 'F' insulation. Terminal box for exhaust fans shall
be explosion proof type

4.5.3 Only one exhaust fan shall be running any point of time. In case of failure of
one fan, the other shall start automatically.

4.5.4 Exhaust fan shall be manufactured in weather resistant polymeric material

and shall be designed for maximum aerodynamic efficiency.

4.5.5 The fan shall be suitable for operation in ambient temperature up to 55⁰C
and shall be fitted with thermal overload protection trip.

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4.5.6 The fan shall be of integrated component design allowing all parts to be
dismantled for cleaning without the use of specialist tools.

4.5.7 Fan shall have a wall louver and shall be provided with back draught
damper.

4.5.8 Capacity of exhaust fan shall be as per approved sizing calculations.

4.6 Interface with Other Systems Like FCS/FGS/IPS/SCADA/UPS etc

4.6.1 DDC shall have provision to receive potential free contacts from building fire
alarm system or F & G system to trip the entire HVAC system.

4.6.2 HVAC common Fault Alarm i.e. Failure of both HVAC units (Potential Free
dry Contact) from DDC to SCADA and FCS.

4.6.3 HVAC Unit Fault Alarm i.e. Failure of each HVAC units (Potential Free dry
Contact) from DDC to SCADA and FCS.

4.6.4 Potential free contacts for battery room exhaust fan failure (if both fan fails)
from DDC panel to each AC and DC UPS unit to inhibit boost charge
operation of battery bank.

4.6.5 Potential free contacts for battery room exhaust fan failure (if any one fan
fails) from DDC panel to SCADA and FCS.

4.6.6 Common Fault alarm from HVAC MCC (combination of all electrical faults
within MCC) to SCADA and FCS.

4.6.7 Signals to SCADA are applicable in case of standalone electrical substations

and FCS in case of process control building.

4.7 Electrical Documents

4.7.1 Vendor shall submit the following electrical documents as a minimum along
with bid.

4.7.1.1 Load list indicating maximum demand figures with rated power, absorbed
power, efficiency and power factor for various loads of HVAC. (indicating
working / standby operation)

4.7.2 GA drawing – 415V LV HVAC MCC with cable entry and mounting details.

4.7.3 GA drawings – DDC panel, Heater panel, VSD etc

4.7.4 Single Line diagram - 415V LV HVAC MCC

4.7.5 Single Line diagram - VSD, Heater Panels as applicable.

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4.7.6 Filled in data sheets for 415V LV HVAC MCC, motors, Exhaust fan, Heater
and VSD as applicable.

4.7.7 HVAC Package and Duct layout

4.7.8 Sub-Vendor list (for electrical equipments)

4.7.9 Vendor shall submit the following electrical documents after Purchase Order
(during detail engineering):

4.7.10 Load list indicating maximum demand figures with rated power, absorbed
power, efficiency and power factor for various loads of HVAC. (indicating
working / standby operation)

4.7.11 GA drawing - 415V LV HVAC MCC with cable entry and mounting details.

4.7.12 GA drawings – DDC panel, Load Break Switch, RCU, Safety switch, Heater
panel, VSD etc with cable entry and mounting details.

4.7.13 415V LV HVAC MCC - Single Line diagram, Wiring / Schematic drawings
with protection and metering, Bill of materials

4.7.14 VSD - Single Line diagram, Wiring / Schematic drawings with protection and
metering, Bill of materials

4.7.15 Heater Panel - Single Line diagram, Wiring / Schematic drawings with
protection and metering, Bill of materials

4.7.16 DDC Panel - Single Line diagram, Wiring / Schematic drawings with
protection and metering, Bill of materials

4.7.17 Filled in data sheets for 415V LV HVAC MCC, motors (including
performance curves), Exhaust fan, Heater and VSD as applicable.

4.7.18 HVAC Package and Duct layout

4.7.19 Cable sizing calculations

4.7.20 Cable Schedule

4.7.21 Interconnection diagram with cable termination details including terminal

numbers of each equipment

4.7.22 Cable route layout

4.7.23 Hazardous Area Certificates ( applicable for exhaust fans)

4.7.24 Inspection and test plans (for electrical equipments)

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4.7.25 Test Procedures (for electrical equipments)

4.7.26 Routine test reports (for electrical equipments)

4.7.27 Sub-Vendor list (for electrical equipments)

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5.0 Appendices
Appendix A: HVAC Typical and General Details
Appendix B: Standard Air Conditioning Test Sheets
Appendix C: SP User- Comment Form

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Appendix A: HVAC Typical and General Details

CONTENTS
Ref Doc Number Description
Figure-A01 : Typical FCU Connection detail.
Figure-A02 : Typical AHU Connection detail.
Figure-A03 : Typical AHU & FCU support.
Figure-A04 : Typical Installation details for Split unit.
Figure-A05 : AHU Arrangement in Plant room typical.
Figure-A06 : Duct Insulation & Cladding details typical.
Figure-A07 : Typical Indoor rectangular Duct support details.
Figure-A08 : Roof slab penetration details.
Figure-A09 : Typical details of duct penetration in Fire wall.
Figure-A10 : Typical Chiller Arrangement details.
Figure-A11 : Piping connection & foundation details for Chiller.
Figure-A12 : Chilled water pipe insulation details.
Figure-A13 : Details for supporting insulated pipe on roller stand.
Figure-A14 : Typical hanger details.
Figure-A15 : Piping connection & foundation details for Pump
Figure-A16 : Control schematic for HVAC control system

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HVAC Typical Details:

Figure – A 01

Figure - A02
Note: AHU room shall be provided with air conditioning.

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Figure - A 03

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Figure – A 04

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Figure – A 05

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Figure – A 0 6 Insulation and cladding details

Figure – A 07

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Figure - A 0 8

Figure – A 09

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Figure No: A10

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Figure No: A11

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Figure No: A12

Figure No: A13

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Figure No: A14

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Figure No: A15

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Figure No: A16

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Appendix B: Standard Air Conditioning Test Sheets

CONTENTS
Ref Doc Number Description
1285-B01 : Air Balance
1285-B02 : Fan Coil Unit System
1285-B03 : Chilled Water Balance
1285-B04 : Chemical Dosing
1285-B05 : Water Chiller Full Load
1285-B06 : Chilled Water Pump
1285-B07 : Centrifugal Fan
1285-B08 : Chilled Water Coil
1285-B09 : Direct Expansion Unit
1285-B10 : Electric Heater Battery
1285-B11 : Humidifier
1285-B12 : DDC Panel
1285-B13 : Sound Levels

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1285-B01 : AIR-CONDITIONING TEST SHEET FOR AIR BALANCE

AIR BALANCE Check Sheet:_____

A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
B. INSPECTION/TEST:
Outlet Design First Test Final Test
Qty. Velocity Qty. Velocity OFF grill Qty. Velocity OFF grill
Ref Size
(l/sec) (m/Sec) (l/sec) (m/Sec) temp.°C. (l/sec) (m/Sec) Temp.°C.

System Total : Limits 0 to 10%

C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & DATE:
SIGN :
PDO REF IND & SIGN : DATE:

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1285-B02 : AIR-CONDITIONING TEST SHEET FOR FAN COIL UNIT

FAN COIL UNIT Check Sheet:_____

A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
B. INSPECTION/TEST:
Current Voltage. Functional check T'
Noise Room Amb.
(AMP) Visual Stat Supply
FCU Fan speed (rpm) (V) level Temp Temp
FCU check set Air (C)
Model (dB) (C) (C)
Ref (C)
No
H M L T' stat T' stat Valve

C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME DATE:
& SIGN :
PDO REF IND & SIGN : DATE:

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 1285-B03 : AIR-CONDITIONING TEST SHEET FOR CHILLED WATER BALANCE

CHILLED WATER BALANCE Check

Sheet:_____
A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
B. INSPECTION/TEST:
Design First Test Final Test
Valve Locat
No ion Flow P Flow %
Flow (l/sec) P (bar) P (bar)
(l/sec) (bar) (l/sec) Design

Limit :- 0 to +10%
1. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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1285-B04 : AIR-CONDITIONING TEST SHEET FOR CHEMICAL DOSING

CHEMICAL DOSING Check

Sheet:_____
A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
B. INSPECTION/TEST: RESULT
1. Pre-treatment
Initial Flush Final Leakage Test
Volume
of water Working Test
(m3) Time (hrs) Strainer System Pressure Pressure Time (hrs)
(bar) (bar)

2. Cleaning:
Descaler type.
Dosage (kg/m3).
Dose.
Time
3. Final Flush:
Time (hrs)
Strainer
System
4. Dosing:
Manufacturer:
Corrosion inhibitor product:
Corrosion inhibitor (kg/m3)
Corrosion inhibitor dose (kg)
Algae/bacteria inhibitor product:
Algae/bacteria inhibitor (kg/m3)
Algae/bacteria inhibitor (kg)
5. Record Final pH. (Limits 7.0-8.0)
C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:
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1285-B05 : AIR-CONDITIONING TEST SHEET FOR WATER CHILLER FULL LOAD

WATER CHILLER FULL LOAD Check
Sheet:_____
A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
MANUFACTURER: TYPE/SIZE:
SERIAL NO: REF NO:
B. INSPECTION/TEST:
Design Test % Design
Water Flow rate
( l/sec)
Inlet Water Temperature
(C)
Outlet Water Temperature
(C)
Inlet Water pressure (bar)
Outlet Water Pressure
(bar)
Compressor running
suction pressure (psi)
Compressor running
discharge pressure (psi)
Ambient Air Temperature
(C)
Compressor Current (amp)
Compressor volt
(v)
L.P. Cut out.

H.P Cut out

Crank case heater

Amps/KW
Condensing temp. °C

Discharge condensing coil

temp.°C
Condenser Fan amp.

Condenser Fan V.

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Condenser Fan rpm.

Suction discharge temp.

°C

Noise in dBA.
Check flow Switch
Notes :
1. Test runs shall be carried out during summer months(May, June, July or August)
over a minimum of 3 days
2. Completed manufacturers start-up and test report sheets shall be attached to this
report
3. For multiple installations, test runs shall include all chillers
C REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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1285-B06 : AIR-CONDITIONING TEST SHEET FOR CHILLED WATER PUMP

CHILLED WATER PUMP Check

Sheet:_____
A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
B. INSPECTION/TEST:
1. PUMP:
MANUFACTURER: TYPE: SERIAL/MODEL NO:
SIZE: REF NO:
LEVELLING & ALIGNMENT Reading Tolerance
Levelling 0.05 mm/m
Radial(Parallel) Misalignment 0.10 mm total indicator
Axial (Angular) Misalignment 0.05mm (150mm dia.)
Design Test % Design
Flow rate (l/sec) (Limits: 0 to 10%)

Speed (rpm)
Head (bar)
Suction pressure
(bar)
Discharge
pressure(bar)
Discharge Pressure(Pd) - Suction Pressure(Ps) = Head
2. MOTOR:
MANUFACTURER: TYPE: SERIAL/FRAME NO:
RATING: KW V A
Design Test
Line voltage (V)
Running current (A)
Speed (rpm)
3. STARTER:
MANUFACTURER: TYPE: SERIAL NO:
OVERLOAD RANGE: OVERLOAD SETTING:
FUSE RATING TIMER SETTING:
C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:
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1285-B07 : AIR-CONDITIONING TEST SHEET FOR CENTRIFUGAL FAN(AHU)

CENTRIFUGAL FAN Check Sheet:_____

A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
B. INSPECTION/TEST:
1. FAN:
MANUFACTURER: TYPE: SERIAL/MODEL NO:
SIZE: REF NO:

No/SIZE OF BELT: TYPE OF BELT: PULLEY CENTRES:

FAN PULLEY SIZE FAN SHAFT SIZE:
KEYWAY SIZE:
Design Test %Design (Difference)
Ex St. Pressure
Speed (rpm)
Supply Air
(m3/sec)
Fresh Air (m3/sec)
Supply Air Volume Test Limits = 0% to +10%.
Supply Static Pressure - Return Static Pressure = ESP
2. MOTOR:
MANUFACTURER: TYPE: SERIAL/FRAME NO:
RATING: :KW :V :A
MOTOR PULLEY SIZE MOTOR SHAFT SIZE:
KEYWAY SIZE:
Line voltage (V)
Running current (A)
Speed (rpm)
3. STARTER:
MANUFACTURER: TYPE: SERIAL NO:
OVERLOAD RANGE: OVERLOAD SETTING:
FUSE RATING TIMER SETTING:
C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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1285-B08 : AIR-CONDITIONING TEST SHEET FOR CHILLED WATER COIL

CHILEED WATER COIL Check

Sheet:_____
A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
MANUFACTURER: COIL REF:
TYPE/SIZE: VALVE REF:
SERIAL NO:
B. INSPECTION/TEST:
1. AIR SIDE:
Design Test % Design
Air Flow (l/sec)
Entering DB/WB
Temperature (C)
Leaving DB/WB
Temperature (C)
Entering Enthalpy, He
(kJ/kg)
Leaving Enthalpy, Hl
(kJ/kg)
Heat from Air (kW)
KW = 1.2 x (m3/sec) x (He - Hl)
2. WATER SIDE:
Design Test % Design
Water Flow (l/sec)
Inlet Temperature, Ti (C)
Outlet Temperature, To
(C)
Heat to Water (kW)
KW = 4.1868 x (l/sec) x (To - Ti)
3. Number of Rows
C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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1285-B09 : AIR-CONDITIONING TEST SHEET FOR DIRECT EXPANSION UNIT

DIRECTR EXPANSION COIL Check Sheet:_____

A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
EVAPORATOR CONDENSATOR
MANUFACTURER:
TYPE/SIZE:
SERIAL NO:
Control Stages: Saturated Suction Temp (C):
B. INSPECTION/TEST:
1. EVAPORATOR:
Design Test % Design

Air Flow (m3/sec)

Entering DB/WB
Temperature (C)
Leaving DB/WB
Temperature (C)
Entering Enthalpy, He
(kJ/kg)
Leaving Enthalpy, Hl
(kJ/kg)

Heat from Air (kW)

KW = 1.2 x (m3/sec) x (He - Hl)

2. CONDENSER:
Record Line Voltage (V).
Record Compressor current (A).
Record Fan current (A).
Record total current (A).
Record suction pressure (kPa).
Record discharge pressure (kPa).
Record refrigerating effect (kW).
Record oil pressure (kPa).
Record entering air temperature (C).
Record section temperature (C).
Record Discharge temperature (C).
Record superheat temperature (C).
continue next page

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Record COP.
Record leaving air temperature (C).
Record LP switch cut-in (kPa).
Record LP switch cut-out (kPa).
Record HP switch cut-in (kPa).
Record HP switch cut-out (kPa).
C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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1285-B10 : AIR-CONDITIONING TEST SHEET FOR ELECTRIC HEATER BATTERY

ELECTRICAL HEATER Check Sheet:_____

A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
MANUFACTURER: TYPE/SIZE:
SERIAL NO: REF NO:
RATING: W V A 1-phase/3-
phase
NO OF STAGES:
B. INSPECTION/TEST:
1. AIR SIDE:
Design Test % Design

Air Flow (m3/sec)

Entering DB/WB
Temperature - Te
(C)
Leaving DB/WB
Temperature - Tl (C)

Heat from Air (kW)

KW = 1.214 x (m3/sec) x (Te - Tl)

2. HEATER:
Record Line Voltage (V).
Record running current (A).
High Temp T' sat cut-out (C).
High Temp T' sat cut-in (C).
C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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1285-B11 : AIR-CONDITIONING TEST SHEET FOR HUMIDIFIER

HUMIDIFIER Check
Sheet:_____
A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
MANUFACTURER: TYPE/SIZE:
SERIAL NO: REF NO:
RATING: :W :V :A 1-phase/3-
phase
B. INSPECTION/TEST:
Design Test % Design
Air Flow (l/sec)
Entering DB
Temperature (C)
Entering WB
Temperature (C)
Entering Moisture
content
Leaving DB
Temperature (C)
Leaving WB
Temperature (C)
Leaving Moisture
content
Moisture to Air
Record Line Voltage (V).
Record running current (A).
C. REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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1285-B12 : AIR-CONDITIONING TEST SHEET FOR DDC PANEL

CENTRALDDC PANEL Check Sheet:_____

A. INDENT/CONTRACT No:
LOCATION: SYSTEM/DUTY:
MANUFACTURER: TYPE/SIZE:
SERIAL NO: REF NO:
INSPECTION/TEST:
CHECK input Out put Function(Status)
Wiring
Interlink with chiller
Interlink with AHU
and FCU
Interlink with pump
Interlink with fire
panel
Interlink with Power
panel
Interlink with
ventilation and
exhaust fan.

Record Line Voltage (V).

Record running current (A).
REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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1285-B13 Standard Air Conditioning Test Sheet – Sound Levels

Contract: Contractor: Location:
A. INDENT/CONTRACT No:
LOCATION:
NOISE RATING CURVES

B INSPECTION/TEST:
Spec Octave Bands (Hz) Test
NR 62.5 125 250 500 1000 2000 4000 8000 NR
Plant On
Plant Off
NOTES
(This Test Sheet should be used only when the noise level is questioned.)
C REMARKS/OBSERVATIONS:

CONTRACTOR :
TESTING ENGINEER NAME & SIGN : DATE:
PDO REF IND & SIGN : DATE:

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4.9 Appendix C: SP User - Comment Form

SP User-Comment Form
If you find something that is incorrect, ambiguous or could be better in an SP, write your
comments and suggestions on this form. Send the form to the Document Control Section
(DCS). They make a record of your comment and send the form to the correct CFDH.
The form has spaces for your personal details. This lets DCS or the CFDH ask you about
your comments and tell you about the decision.
SP Details Title Issue Date:
Number:

Page number: Heading Number: Figure Number:

Comments:
Suggestions:

User’s personal details

Name: Ref. Ind: Signature: Date:
Phone:
Document Control Section Actions
Comment Number: Dates CFDH
Recd: To CFDH: Ref. Ind:

CFDH Actions
Recd Date: Decision: Inits: Ref. Date:
Ind:
Reject:
Accept, revise at next issue:
Accept, issue temporary
amendment
Comments:

Originator Date: Inits: Document Date: Inits:

Advised: Control Section
Advised:

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