COMPANY PROFILE

AKHWAN ELECTRO MECHANICAL WORKS

& HVAC CONTRACTING

SINCE 2006

License No. 33518, Showroom No.7

Old Industrial Area Umm Al Quwain U.A.E
Phone No. 00971-6-7404800
Email – akhwanhvac@gmail.com
WEBSITE: www.usmanemsc.com
Email ID: usmanemsc@gmail.com

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 INTRODUCTION LETTER

We take a opportunity of introducing ourselves as a integrated, experienced and a

well professional electromechanical works. We specialize in the entire electro-
mechanical works of all types of project, viz. Hospitals, Hotels, Shopping Malls,
Residential Complexes and Private Commercial/ Buildings, Villas and Factories.

We as AKHWAN Electro-mechanical Works & Contracting are specialized in the

contracting works and services related to the above mentioned facilities carrying
out HVAC(All type of Duct fabrications, Chillers, Chilled water piping, Copper
piping, Cladding, Heat exchanger & pump room installation, Designing and
estimation) Fire Fighting Systems(Maintenance), Overhauling with a proven track
records of excellent workmanships and a dedicated customer satisfaction.
We have worked with following Project Management Offices, Clients and
Consultants.
1. NAKHEEL.
2. AMANA CONTRACTING L.L.C.
3. AL MEHAR CONTRACTING LLC
4. AL BADR CONTRACTING CO L.L.C
5. DUBAI ELECTRICITY & WATER AUTHORITY ( DEWA )
6. LINK MIDDLE EAST L.T.D.
7. DOME ENGINEERING CONSULTANCY
8. EMARET AL SHARQ ARCHITECTURE CONSULTANT
9. AL JADEED ENGINEERING & CONTRACTING CO LLC
10.CARLTON HOTEL RESORT SUITES
11. EASTERN INTERNATIONAL L.L.C
12. DOLPHIN CONTRACTING.
13. HI-TECH GROUP OF COMPANIES.
14. INTERNATIONAL ELECTROMECHANICAL SERVICES LLC
15. AL DARWISH CONTRACTING
16 EASTERN INTERNATIONAL L.L.C
The objective of the company for a diverse operation and with a greater growth
remains unchanged with the previous year taking into consideration the quality
work, professional competence in offering complete Electromechanical Solutions at
a optimum level and profitability with a greater customer satisfaction.

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 OBJECTIVE AND GOALS THAT WE STRIVE TO ATTAIN

• To maintain a constant growth rate.

• To offer single window solution to the client’s complete Electromechanical
requirement.
• To ensure an committed quality and time schedule in all the projects and by
maintaining honesty, integrity and social awareness in all the transaction.
To ensure repeated orders from satisfied customers.

We hereby confirm our deep interest to associate with your esteemed company to
carry out the above services in strict conformity to your project specifications and
in compliance with international standards.

We look forward for your kind consideration to be your HVAC Contractor for your
projects and for healthy business relationship with your esteemed organization.

Thanking you and assuring you of our best services at all times.

Yours Faithfully,
From AKHWAN ELECTRO MECHANICAL WORKS & CONTRACTING.

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 A MESSAGE ESTABLISHMENT OWNER

WE live in world of continual change. New technologies replaces old, freshthinking replaces
yesterday’s idea and shifts driven new approaches.

Our future is evolving, yet, amid all the changes, one thing has remained constant; Our
sustainability focus, in all varied forms, remain STRONG.

Our focus on sustainability has shown us that the powerful outcomes are possible through the
concrete efforts of our co-worker, partners and stakeholders.

With new Editions & Visions, we are now dealing, Manufacturing of ducts & ducting solutions for air-
conditioning set-up, Total cladding & Ventilation Solutions along with repairing and rehabilitation &
supply of A.C’s, Chillers, H.V.A.C, Package Units, AC compressors, Lathe & Fabrication Solutions.

We are providing the best quality service with the professionally qualified & trained staff for all Electro
Mechanical Services, Contracting & Manufacturing.

By trusting our services we ensure that the best services & expertise will reduce the maintenance cost
for the customer’s costly equipment. Our dedicated team is always enthusiastic to assist you round the
clock 24/7.

I have every confidence that our dedication and spirit will go forward as the business association with
our precious current & future clients will complete its cycle of completion and satisfaction.

I am certain that our company will carry with it, a sustainable focus on improving Services, Practices
and Standards.

“Change is a Constant, But So Is DEDICATION To Make a Difference”

Thank you.

Eng. Usman Butt

Establishment Owner

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 JOINT ESTABLISHMENTS

Date of Establishment : 2006

Legal Status : Sole Establishment

License No. : 596991

Address : SHOP NO 7,8 . H 01 BUILDING

CHINA CLUSTER INTERNATIONAL CITY, DAI
P.O. Box No.22084, Dubai, U.A.E.

Branch : AKHWAN ELECTRO MECH. WORKS CONT.

Showroom Shop No. 7, Old Ind. Area Umm Al Quwain
AKHWAN License. 33518

Al-Harmain Electro Mechanical Services. License No:C.R #4030141848

Email: haramex@hotmail.com(Prince Mutabe Street, Jeddah, Saudi Arabia)

Experience : 17 Years (Dubai)

1 YEAR UMM AL QUWAIN
: 26 Years (Saudi Arabia)

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 COMPLETED PROJECTS

COURTYARD MARRIOT HOTEL AL SERKAL GROUP

GOV. HOSPITAL MIDRIFF CARLTON RESORTS SUITS

AL GHADEER DEVELOPMENT IMDAAD L.L.C

PHASE 1

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DREAM LAND TOWER ELITE GLOBAL HOLDING L.T.D.

BAFCO

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 LIMITLESS BUILDING, DOWNTOWN JABEL ALI
(2 G + 26 FLOORS + ROOF)
CONTRACTOR
EASTERN INTERNATIONAL LLC
CONSULTANT
BEL-YOAHAH CONSULTANCY
WORK DESCRIPTION
1. COMPLETE NEW SUPPLY AND INSTALLATION OF GI AND
FIRE RATED DUCT & CHILLED WATER PIPING .
2. INSTALLATION OF FAHU ,AHU ,FCU , EXHAUST FAN &
PUMP ROOM .
3. TEST AND COMMISSIONING.

CONTRACTOR
AL MEHAR CONTRACTING LLC
CONSULTANT
AL GAFRY CONSULTANTS
WORK DESCRIPTION
1. COMPLETE NEW SUPPLY AND INSTALLATION OFPRE
INSULATED DUCT.
2. INSTALLATION OF DUCTED AND DECORATIVE TYPEA/C
UNITS.3. TEST AND COMMISSIONING.

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Project: INTERNATIONAL SCHOOL OF CREATIVE SCIENCE- NADD AL SHIBA-DUBAI
Main Contractor : Darwish Engineering Emirates
Consultant : Arab & Turk International

Project: GHAYAATHI COMMUNITY HOSPITAL, ABU DHABI,UAE.

Main Contractor : AMANA WALBRIDGE

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ABU DHABI MEDIA SHOWROOM
CONTRACTOR
AL MEHAR CONTRACTING LLC
CONSULTANT
BEL-YOAHAH CONSULTANCY
WORK DESCRIPTION
1. COMPLETE NEW SUPPLY AND INSTALLATION OF GI AND FIRE
RATED DUCT.
2. SUPPLY & INSTALLATION OF DUCTED AND DECORATIVE TYPE A/C UNITS.
3. TEST AND COMMISSIONING.

CONTRACTOR
AL MEHAR CONTRACTING LLCCONSULTANT
BEL-YOAHAH CONSULTANCY
WORK DESCRIPTION
1. COMPLETE NEW SUPPLY AND
INSTALLATION OF PRE INSULATEDDUCT.
2. INSTALLATION OF DUCTED AND
DECORATIVE TYPE A/C UNITS.
3. TEST AND COMMISSIONING.

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 CONTRACTOR
HI-BUILD CONSTRUCTION LLC
CONSULTANT
EMARATI ENG. CONSULTANCYWORK

DESCRIPTION

1. COMPLETE NEW SUPPLY AND

INSTALLATION OF PRE INSULATED
DUCT.
2. INSTALLATION OF DUCTED AND
DECORATIVE TYPE A/C UNITS.
3. TEST AND COMMISSIONING.

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Project: LYCEE FRANCIAS INTERNATIONAL GEORGES POM-PIDOU
Contractor: TALIH CONTRACTING COMPANY
Consultant: EMARET AL SHARQ ARCHITECTURE

Project: AL MEYDAN VILLA PROJECT

Contractor: EMW
Consultant: AE7

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CLIENT: DUBAI PROPERTIES CONTRACTOR: AMANA CONTRACTING
CONSULTANT: KLING CONSULT
WORK DESCRIPTION
CLADDING OF DUCTS AND CHILLED WATER PIPES 4 B

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WE DO SUPPLY & TRADING ALL TYPE OF NEW AIR CONDITIONING MACHINES DEALS WITH ALL BRANDS
WITH COMPETITIVE PRICES. MAKING SURE AVAILABILITY WITH FREE COMPREHENSIVE DELIVERY.

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PRELIMINARY PROJECT EXECUTION PLAN

The execution of project is done professionally by not only carrying out all our
contractual obligations but also with an intent that the installation would pass with
flying colors under the ultimate scrutiny of the End user.

A project team would be ear marked to handle the project. This team will be well
headed by an well experienced project manager if not then by a well experienced
project engineer. The project manager would be assisted by the site based and office
based team with in house engineers.

• DESIGN MANAGEMENT

We have a in-house Design Department equipped with AutoCAD drafting stations,

printing and plotting tools.

Each service of HVAC is centered by a team of specialist engineers supported by

well experienced draftsman.

The Design team is well experienced and is able to handle various design concepts
for HVAC in coordination with the structural & architectural features as per local
statutory regulations.

The Design team will also liase with the Client’s or the Consultant’s Engineers for
clarifications on design concepts, shop drawings and material submissions.

• PROCUREMENT STRATEGY

Being a Electromechanical contractor we have in our stock most of the Fist Fix
Items.

For the items related to specific projects, the lead times are determined from
various vendors. Material submissions are made giving adequate time for review by
the approver. The ordering schedule is determined by on the approved construction
programmed.

Purchase orders are issued with a clear scope of work based on approved technical
submissions and quantities derived from approved shop drawings.

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 PRELIMINARY PROJECT EXECUTION PLAN (cont...)

• MANUFACTURING SEQUENCING

The basic manufacturing programmed of HVAC services shall follow the Main
Contractor’s civil construction. The Planning and Programming will be carried out
by planning engineer well versed with project management software via Primevera,
MS - Projects etc.

The Various HVAC activities are divided into various stages under:

1. Embedded services on structures - like openings, pipe etc.

2. HVAC First Fix Items - This activity comprises of various services like
anchoring supports for services, ductwork etc.
3. HVAC Second Fix Items- This activity comprises of various services over the
ceiling taking into consideration the false ceiling clearance.
4. HVAC service installations in low level - This activity comprises of all ser-
vices below false ceiling levels ad those on foundations. Viz. Fixtures, Pumps,
Chillers, Structures etc.
5. HVAC Final Fix - This activity comprises of installation of decorative and
terminal devices like light fixtures, grills, diffusers, thermostats, and low current
devices etc. This activity follows the completion of fit out activity by the main
contractor.
6. Inspection by the Consultant.
7. Inspection by Contractor.
8. Commissioning of various systems.
9. Project Handover to Client.

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 PRELIMINARY PROJECT EXECUTION PLAN (cont...)

• STAFF RESOURCING & ORGANIZATION CHART.

The type and no. of resources required are established based on activities as per the
HVAC Manufacturing program. The detailed labor histogram covering the entire
contract durations generated and forwarded for approval.

• QUALITY MANAGEMENT PROCESS AND PROCEDURE

Our Quality plan is attached for the review.

• SAFETY MANAGEMENT PROCESS AND PROCEDURE

Our Safety plan is attached for review

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Contracting
Services

Chillers,
Package Ducted split
HVAC Units,
Coiling
Deco unit
FAHU
Towers

All Types Chilled Pump room,

and Brands Water Piping Heat
of AC
Selling
Copper Exchanger
piping installation

GI Duct Pre Arc welding

insulated co2 welding Aluminium
Duct, Gas welding Cladding
Fabrication

Designing
Secondary Machine
pumps
& Primary
Shop,
Estimation pumps Lathe

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 DUCT MANUFACTURING

It is our goal to make sure of 100% customer satisfaction from

Mission Statement: initial request for quote, & all the way through the ease of
manufacturing & installation of our products in the field.

Implementing a project and procedures management system that

will be utilized on major projects, in the form of project execution
Quality Assurance: plan. This system will include all aspect of engineering, procurement,
cost and schedule, quality assurance, project financial control as well
as a comprehensive reporting system.

Management System: Key Factors: Job Estimates, CAD Drawings, Job Scheduling, Job
Quality Checks, Etc.
Management systems providing the framework for contrac t work
definition, assignment of work responsibilities and establishment of
budget, cost and schedule control. This will also deliver a summary
of planned versus actual accomplishment for price, schedule and
related technical achievement to provide managers with continuous
visibility of performance.
Product Line:
❑ Rectangular ducts and ❑ Single Wall Round
fittings. ❑ Single Wall Flat Oval
❑ Round ducts and fittings. ❑ Double Wall Round
❑ Sheet metal materials. ❑ Double Wall Flat Oval
❑ Sealants and gaskets. ❑ Specialty Products
❑ Hangers and supports. Etc.
❑ Seismic-restraint devices

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 PRE - INSULATED DUCTS

❑ Pre-insulated aluminum duct is specialized in the air distribution fields and

the answer to economical, technical, and constructive question.
❑ Many different material and system such as composite, PVC etc. had been
developed as an alternative to the galvanized sheet metal used traditionally.
❑ Pre-insulated aluminum duct is the solution. It is a sandwich panel composed
of a layer base from good fire retardant rigid polisocyanurate foam covering
both sides with aluminum foil.
❑ The aluminum guarantees sturdiness and with sand corrosion in long term
use.
❑ Polyisocyanurate pre-insulated duct has been developed and spread around
the world. It’s application has been gradually extended to all type of air
distribution system such as industrial , commercial and civil.

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 CLADDING

Mission Statement:
It is our goal to make sure of 100% customer satisfaction from
initial request for quote, & all the way through the ease of
manufacturing & installation of our products in the field.
Quality Assurance:
Implementing a project and procedures management system
that will be utilized on major projects, in the form of project
execution plan. This system will include all aspects of
engineering, procurement, cost and schedule, quality
assurance, project financial control as well as a
comprehensive reporting system.
.

Cladding Alloy Demagnetizing

Specification
Requirements for
Cladding Products

Dimensions and Cladding and Wall

Tolerances of Clad Pipe Thickness

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 PRODUCTION METHOD

• Longitudinally • Hot Roll Bonding.

welding of clad plate. • Explosive Bonding.
• Centrifugal casting. • Weld Overlaying.
• Seamless Pipe Mill
Production Methods.
• Explosive Bonding.

CLAD CLAD
PIPES PLATES

CLAD CLAD
BENDS FITTINGS
• Manufacturing of Weld Overlaying.
Bends from clad pipe. • Hot Isotactic
• Manufacturing of Pressing.
Bends from Lined • Manufacturing from
pipe. Clad plate or Pipe.

Fabricating Clad Vessels

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DUCTWORK FITTINGS

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 DUCTWORKWORKSHOP
SETUP AND PROCEDURE

QUALITY STANDARDS
AND SCOPE OF WORK

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 QUALITY STANDARDS
AND SCOPE OF WORK
Air
Duct Works Insulations Ventilation
Conditioning

❑ We follow the standards of air tightness required by DW.144

❑ We use suitable materials for the working temperature & pressure of systems within
which it is installed and shall be tear resistant.
❑ The materials we use are always in accordance with the manufacturers technical data
sheet, material safety data sheet and application method statement.
❑ We always take measures and proofed against Rotting, mould, fungus growth and attack
by vermin.
❑ Always consider and take adequate precautions against any hazard to health involved in
the use of any cleaner, adhesive or material in connection with the application and
handling of insulation material.
❑ Adequate consideration take in using the insulation materials and finishes that shall not
produce smoke or toxic fumes when subject to fire (as British Standards). The smoke
obscuration rating of insulating materials not greater than 5% in accordance with BS EN
ISO 5659-2.
❑ We always follow the strict execution accordance with manufacturer’s
recommendations including all seals and adhesive, take care of compatibility of such
adhesives with the insulation.
❑ Always take measures (as our quality standards & policy) to clean, dry and free from rust
and other foreign matters from all surfaces to be insulated.
❑ Copper pipe work always thoroughly cleaned to remove all traces of surplus flux dust
and debris.
❑ Special attention given to finished appearance of all insulated areas, and remove any
rough, irregular and badly finished surfaces which shall present a neat and symmetrical
appearance with all pipe lay outs.
❑ Particular attention given to maintain the reliability and continuity of vapour barriers.
❑ Measures always taken to ensure the close fitting to all pipe work, and the insulation
shall match the outside diameter of pipe work concerned and all joints shall be properly
sealed.

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 GRILLS AND DIFFUSERS

❑ We always take care the calculation, design and manufacture the true size for reasonable
throw and velocity at maximum flow conditions, but with consideration to avoid
”Dumping” at minimum flow conditions.

❑ All Grills & diffusers are always adjusted to the face of register or grill

❑ Take care for detailing air flow registered noise level of air supplies and extract grills and
plenum boxes under spigot setup and conditions and at the operational air velocities.

AIR CONDITIONING &

VENTILATION

❑ As our quality policy, we always take care the insulation specification provided by the
client under “Air Conditioning & Ventilation Specifications”.
❑ We always use insulation materials that shall not omit smoke or toxic fumes in the event
of fire.
❑ In our QUALITY Services we Design, Supply, Install, Test, Commission, Adjust, Balance
the Chillers, Central Air Conditioning, Ventilation systems etc. for satisfactory
performance.

❑ The purpose of the design check is to ensure the material used and the installation is in
line with the design & standards intent, for the correct functioning of the installed
system(s).

❑ All the materials which we use to install in the project, are always fully in compliance
with local authority’s rules & regulations.

❑ Full safety precautions taken during welding & cutting operations, full precautions taken
to prevent fire i.e. fully charged 5kg carbon dioxide extinguisher, protect wooden
structure with fire proof blanket etc.

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 FABRICATION AND
INSTALLATION OF UNITS
Determine the conditions for which low energy positive input ventilation will
Mission Statement : save energy whilst providing adequate ventilation through an understanding of
its performance.

Save Energy
Key Factors : Remove Moisture (Dehumidification)

Good Source Of Ventilation Air

Types of Ventilation Systems:

Exhaust Ventilation

Balanced Ventilation

Exhaust Ventilation

Our Services & Manufacturing Expertise & Supplies in Ventilation Systems

Energy-recovery Ventilation

Heat-recovery Ventilation

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OUR SERVICES & MANUFACTURING
EXPERTISE & SUPPLIES IN
VENTILATION SYSTEMS

• Duct Work
• Supply Ducts
DUCTS • Outside Air Ducts
• Exhaust Ducts
• Ventilation Ducts

• Continual Ventilation
• Intermittent Ventilation
VENTILATIONS • Mechanical Ventilation
• Continuous Ventilation
• Natural Ventilation

• Multi-port Exhaust
• Single Port Exhaust
EXHAUST VENTILATION • Bath Exhaust
• Passive Vent
• Central Exhaust

PORT • Natural Ventilation

• Multi-port Supply
(Exhaust or Supply) • Forced-air Supply

• Local Exhaust Fan

• Forced-air Fan
FANS • Ventilation Fan (Exhaust Or Supply)

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 EQUIPMENT COMMISSIONING
EXPERTISE
▪ AC PIPING SYSTEMS

• AC Copper Piping
• M.S. Chilled Water Piping Systems

▪ Ductwork.
▪ Variable Frequency Drives.
▪ Packaged Roof Top Air Conditioning Units.
▪ Split System Air Conditioning Units.
▪ Air Handling Units.
▪ Fan Coil Units.
▪ Computer Room Units.
▪ Fans
▪ Fire Damper
▪ Indoor Air Quality
▪ Automatic Temperature Control System / Thermostats.
▪ Testing, Adjusting & Balancing Work.
▪ PLC Card Control Systems
▪ Chiller Commissioning

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 CHILLER COMMISSIONING
EXPERTISE

❑ General
Ensure that individual components are installed and integrated to operate on a system level per the
design intent and sequence of operations.
❑ Sensors
Verify that the sensor installation and calibration is sufficient to achieve the design control strategies.

❑ Safeties, Interlocks, and Alarms

Verify that all safeties, interlocks, and alarms are programmed (or hard-wired, if applicable) and
functioning correctly. Safety and interlock tests, as well as some test procedures and loop tuning efforts
(for example, high or low refrigerant cut-out set points, emergency shut-down procedures, and
failure/back-up system operation)

❑ Unit Capacity
We make sure that the chiller meets the specified performance requirements for temperature or part-load
operation, as well as specified energy efficiency requirements.

❑ Staging
• We validate that isolation valves are installed and operating correctly.
• We ensure that the chillers and primary CHW pumps stage up and down appropriately, per the
sequence of operations.
• We make sure that the time delay between chiller start/stop commands follows the design sequence of
operations.

❑ Reset Controls
• Verify proper reset parameters, which are verified per the design sequence of operations.
• Verification of proper coordination between individual set points and reset strategies. The chilled water
temperature reset strategy to coordinated with discharge air temperature (DAT) reset for each air
handling unit.
• Corroborate that the chilled water supply temperature reset does not adversely impact supply air
dehumidification.

❑ Control Accuracy and Stability

• Proper control sequence and integration of all components (including set points and reset strategies,
start-up / shut down procedures, and time delays).
• PID loops generate the proper set points (e.g. CHW temperature) based on the reset parameters.
• All PID control loops achieve stability (i.e. no hunting) within a reasonable amount of time (typically
no more than five minutes) after a significant load change such as start-up and automatic or manual
recovery from shut down.

❑ Component-Level Testing.

❑ System-Level Testing.

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KEY PREPARATIONS AND CAUTIONS
Successful execution of the chiller functional performance tests .
Testing chilled water temperature reset strategy when there is minimal to no cooling load.
Resetting the chilled water temperature to save chiller energy can result in a loss of humidity control with-
in the building.

NECESSARY INSTRUMENTATION
Temperature measurement devices (hand-held devices to calibrate existing sensors)
Differential pressure measurement devices (to test installed flow meters)
Amperage and voltage measurement devices (for calculating chiller input power)
Flow measurement devices (installed or hand-held devices to measure water flows)
Data loggers (to supplement existing sensors to verify system operation)

CHILLER SYSTEM PRE-FUNCTIONAL

AND FUNCTIONAL TEST
PROCEDURES
Calibration and Leak-By Test Procedures.
Chilled Water System Verification Test Procedure.
Standard Functional Tests for Chilled Water Systems.
Verification and Functional Performance Test Plan for EMS.
Chiller Pre-functional Checklist and Functional Performance Verification.
Chiller Procedures.
Packaged Air-Cooled Chiller.
Chiller System Functional Test.
Chilled Water System Sequence of Operations.
Air-Cooled Chiller Functional Tes.t
DDC Commissioning Acceptance Procedures: Standard Chilled Water System Start/Stop Control.
Component-Level Functional Test Procedures.
Chilled Water Piping Pre-functional Checklist.
Hot Water System Pump Test.
Chilled Water System Pump Test.
Condenser Water System Pump Test

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 HVAC SYSTEMS AND COMPONENTS
Perimeter Outside Air Ventilation Systems.
Perimeter ventilation units have self-contained DX package units or air-handling units with fan section
having variable speed drive, chilled water cooling coil, hot water heating coil, enthalpy heat recovery
wheel, or desiccant wheel and supply air filtration. The perimeter ventilation units provides 100-percent
outside air. Reheat is hot gas bypass, a heat pipe or a run around coil. Chilled water got to be generated by
an air-cooled chiller or a 24-hour chiller. If a desiccant wheel is used for controlling the specific humidity
discharge at the wheel, condenser reheat shall be used for regeneration of the desiccant, along with
minimum electric backup. Supply air dew point leaving the unit shall be maintained at 10°C (50°F) and
the supply air dry bulb temperature leaving the air-handling unit shall be a minimum of 21.1°C (70° F)
and not greater than 25.6°C (78° F) during occupied hours. During occupied hours, this unit shall operate
to deliver conditioned ventilation air and maintain positive pressure in the perimeter zone with respect to
outside air pressure.

During unoccupied hours, the unit shall run at 40 percent of its capacity to provide conditioned air at 10°C
(50° F) dew point and at least 21.1°C (70°F) to help maintain positive pressure in the perimeter zone with
respect to outside air. In both the occupied and unoccupied modes the system shall operate to adjust the
airflow as required to maintain a differential positive pressure in the perimeter zone relative to the
prevailing pressure outside the building. When the outside air dew point drops below 2.8°C (37°F), the
unit shallhave the capacity to maintain neutral pressure with respect to the outside by exhausting relief air
from
the return duct system. The ventilation unit shall have self-contained microprocessor controls capable of
connecting to and interoperating with a BACnet or LONWORKS direct digital control (DDC) Building
Automation System. It shall also be equipped with dampers to set the design airflow through the unit, and
also an analogue or digital display which measures and displays the amount of air flowing through the unit
continuously.

Interior Outside Air Ventilation Systems.

Interior ventilation units contained DX packaged units or air-handling units with chilled water-cooling
coil, hot water heating coil, and supply air filtration. Interior ventilation units shall incorporate enthalpy
heat recovery wheel or desiccant wheel, heating coil, and a cooling coil. Heat recovery shall include use of
building relief and exhaust air. Utilize condenser waste heat for desiccant regeneration. The supply air from
the ventilation units shall be ducted to the return plenum section of the air handling unit(s) serving the
interior zones. Supply air dew point leaving the unit shall be maintained at 10°C (50°F) and the supply air
dry bulb temperature shall be a minimum of 21.1°C (70° F) and not greater than 25.6°C (78° F). During
occupied hours, this unit shall operate to provide conditioned ventilation air. The unit shall be inoperative
during unoccupied hours. The unit shall have air-monitoring devices to indicate that the supply air is al-
ways 10 percent greater than the exhaust/relief air. The dedicated ventilation unit shall have self-contained
microprocessor controls capable of connecting to and interoperating with a BACnet or LONWORKS
Direct Digital Control (DDC) Building Automation System. It shall also be equipped with dampers to set
the design airflow through the unit, and also an analog or digital display which measures and displays the
amount of air flowing through the unit continuously.

Fan Coil System.

For perimeter spaces, provide four-pipe fan coil units with cooling coil, heating coil, 35 percent efficiency
filters, internal condensate drain, and overflow drain. Unit shall have self-contained microprocessor
controls and shall be capable of connecting to and interoperating with a BACnet or LONWORKS Direct
Digital Control (DDC) Building Automation System. Fan coil units shall be capable of operating with unit
mounted or remote mounted temperature sensor.

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 Fin Tube Heating Systems. When fin-tube radiation is used, reheat should not be featured with perimeter air
distribution systems. Fin-tube radiation shall have individual zone thermostatic control capableof connecting to
a self-contained microprocessor that can interface with a BACnet or LONWORKS Direct Digital Control (DCC)
Building Automation System.

Variable Volume System with Shutoff Boxes. Variable Air Volume (VAV) systems with full shutoff VAV
boxes shall be used for perimeter zone applications only. VAV shutoff boxes shall be used only with the
perimeter air distribution systems in order to eliminate the need for reheat. The air-handling unit and
associated VAV boxes shall have self-contained microprocessor controls capable of connecting to and
interoperating with a Direct Digital Control (DDC) Building Automation System.

Variable Volume System with Fan-Powered Boxes.

Variable air volume (VAV) systems with fan-powered VAV boxes may be used for both perimeter and
interior zone applications. The air-handling unit and associated VAV boxes shall have self-contained
microprocessor controls capable of connecting to and interoperating with a BACnet or LONWORKS
Direct Digital Control (DDC) Building Automated System. Fan powered boxes shall be equipped with
a ducted return, featuring a filter/filter rack assembly and covered on all external exposed sides with
two-inches of insulation. The return plenum box shall be a minimum of 61 mm (24 inches) in length
and shall be double wall with insulation in-between or contain at least one elbow where space allows.
Fan-powered boxes may have hot water heating coils used for maintaining temperature conditions in
the space under partial load conditions. Fan powered boxes located on the perimeter zones and on the
top floor of the building shall contain hot water coils for heating.

Variable Volume System with Fan-Powered Boxes.

Variable air volume (VAV) systems with fan-powered VAV boxes may be used for both perimeter and
interior zone applications. The air-handling unit and associated VAV boxes shall have self-contained
microprocessor controls capable of connecting to and interoperating with a BACnet or LONWORKS
Direct Digital Control (DDC) Building Automated System. Fan powered boxes shall be equipped with
a ducted return, featuring a filter/filter rack assembly and covered on all external exposed sides with
two-inches of insulation. The return plenum box shall be a minimum of 61 mm (24 inches) in length
and shall be double wall with insulation in-between or contain at least one elbow where space allows.
Fan-powered boxes may have hot water heating coils used for maintaining temperature conditions in
the space under partial load conditions. Fan powered boxes located on the perimeter zones and on the
top floor of the building shall contain hot water coils for heating.

Under floor Air Distribution System. Under floor air distribution systems incorporate variable air
volume(VAV) units designed to distribute the supply air from under the floor using variable volume
boxes or variable volume dampers running out from under floor, ducted, main trunk lines. Air shall be
distributed into the space through floor-mounted supply registers that shall be factory fabricated with
manual volume control dampers. Supply air temperature for under floor systems shall be between 10°C
(50°F) dew point and 18°C (64°F) dry bulb. For perimeter under
floor systems, provide fan coil units or fin tuberadiators located beneath the floor with supply air grilles
or registers mounted in the floor. The air-handling unit, VAV boxes, and variable volume dampers shall
have self-contained microprocessor controls capable of connecting to and interoperating with a BACnet
or LONWORKS direct digital control(DDC) Building Automation System. The maximum zone size of
an under floor air distribution systemshall not exceed 2,360 l/s (5,000 CFM).

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Under floor Air Displacement System. Under floor air displacement systems shall incorporate variable
air volume (VAV) units designed to distribute the supply air from under the floor using variable volume
boxes or variable volume dampers running out from under floor, ducted, main trunk lines. The VAV
boxes or control dampers shall be hard ducted or connected directly to the main trunk lines. Air shall
be distributed into the occupied space through floor-mounted, low-turbulence, displacement flow, swirl
diffusers and shall contain a dust collection basket situated below the floor. Supply air temperature for
under floor systems shall be 10°C (50°F) dew point and 18°C (64°F) Dry Bulb. For perimeter under
floor systems, provide fan coil units or fin tube radiators located beneath the floor with supply air
grilles or registers mounted in the floor. The air-handling unit, VAV boxes, and variable volume
dampers shall have self-contained microprocessor controls capable of connecting to and interoperating
with a BACnetor LONWORKS Direct Digital Control (DDC) Building Automation System. The
maximum capacity ofan under floor air distribution system shall not exceed 2,360 l/s (5,000 cfm).

Heat Pump Systems. Console perimeter heat pump system(s) may be considered for the perimeter zone.
For the interior zone either a packaged heat pump variable volume system or a central station air
handling unit with cooling-heating coil with VAV boxes will be considered. Condenser water loop
temperatures should be maintained between 15°C (60°F) and 27°C (80°F) year round, either by
injecting heat from a gas fired, modular boiler if the temperature drops below 15°C (60°F) or by
rejecting the heat through a cooling tower if the temperature of the loop rises above 35°C (95°F) dry
bulb. Outside air shallbe ducted to the return plenum section of the heat pump unit. Heat pumps shall be
provided with filter/ filter rack assemblies upstream of the return plenum section of the air-handling
unit.

AIR HANDLING UNITS

Air-handling units shall be sized to not exceed 11,800 l/s (25,000 cfm). Smaller units are encouraged to
facilitate flexible zone, particularly for spaces that involve off-hour or high-load operating conditions.
To the extent possible, “plug-n-play” AHU configurations should be considered, facilitating easy future
adaptations to space-load changes. Psychrometric analyses (complete with chart diagrams) shall be
prepared for each air-handling unit application, characterizing full and part load operating conditions.
Air-handling unit/coil designs shall assure that conditioned space temperatures and humidity levels are
within an acceptable range, per programmed requirements, and ASHRAE Standards 55 and 62.
Depending on sensible heat ratio characteristics, effective moisture control may require cooling coil air
discharge dew point temperatures as low as 10°C (50°F). As required, provide face-by-pass or heat
recovery features to re-heat cooling coil discharge temperatures for acceptable space entry. Provide a
directform of re-heat and/or humidification only if space conditions require tight environmental control,
or if recurring day-long periods of unacceptable humidity levels would otherwise result.
Supply, Return and Relief Air Fans: Centrifugal double width double-inlet forward curved and airfoil
fans are preferable for VAV systems. All fans shall bear the AMCA seal and performance shall be based
on tests made in accordance with AMCA Standard 210. Fans should be selected on the basis of required
horsepower as well as sound power level ratings at full load and at part load conditions. Fan motors shall
be sized so they do not run at over controller load anywhere on their operating curve. Fan operating
characteristics must be checked for the entire range of flow conditions, particularly for forward curved
fans.Fan drives shall be selected for a 1.5 service factor and fan shafts should be selected to operate
below the first critical speed. Thrust arresters should be designed for horizontal discharge fans
operating at high static pressure.

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Coils:
Individual finned tube coils should generally be between six and eight rows with at least 2.1 mm between
fins (12 fins per inch) to ensure that the coils can be effectively and efficiently cleaned. Dehumidifying
coils shall be selected for no more than negligible water droplet carryover beyond the drain pan at design
conditions. All hot water heating and chilled water cooling coils shall be copper tube and copper finned
materials. Equipment and other obstructions in the air stream shall be located sufficiently downstream of
the coil so that it will not come in contact with the water droplet carryover. Cooling coils shall be selected
at or below 2.5 m/s face velocity (500 fpm) to minimize moisture carryover. Heating coils shall be
selected at or below 3.8 m/s face velocity (750 fpm).

Drains and Drain Pans:

Drain pans shall be made of stainless steel, insulated and adequately sloped and trapped to assure drain-
age. Drains in draw-through configurations shall have traps with a depth and height differential between
inlet and outlet equal to the design static pressure plus 2.54 mm (1 inch) minimum.
Filter Sections: Air filtration shall be provided in every air handling system. Air-handling units shall
have a disposable pre-filter and a final filter. The filter media shall be rated in accordance with ASHRAE
Standard 52. Pre-filters shall be 30 percent to 35 percent efficient. Final filters shall be filters with 85 per-
cent efficiency capable of filtering down to 3.0 microns per ASHRAE 52. Filter racks shall be designed to
minimize the bypass of air around the filter media with a maximum bypass leakage of 0.5 percent.
Filters shall be sized at 2.5 m/s (500 FPM) maximum face velocity. Filter media shall be fabricated
so that fibrous shedding does not exceed levels prescribed by ASHRAE 52. The filter housing and all
air-handling components downstream shall not be internally lined with fibrous insulation. Double-wall
construction or an externally insulated sheet metal housing is acceptable. The filter change-out pressure
drop, not the initial clean filter rating, must be used in determining fan pressure requirements.
Differential pressure gauges and sensors shall be placed across each filter bank to allow quick and
accurate assessment of filter dust loading as reflected by air-pressure loss through the filter and sensors
shall be connected to building automation system.

UVC Emitters/Lamps:

Ultraviolet light (C band) emitters/lamps shall be incorporated downstream of all cooling coils and above
all drain pans to control airborne and surface microbial growth and transfer. Applied fixtures/ lamps
must be specifically manufactured for this purpose. Safety interlocks/features shall be provided to limit
hazard to operating staff.
Access Doors: Access Doors shall be provided at air handling units downstream of each coil, upstream of
each filter section and adjacent to each drain pan and fan section. Access doors shall be of sufficient size
to allow personnel to enter the unit to inspect and service all portions of the equipment components.
Plenum Boxes: Air-handling units shall be provided with plenum boxes where relief air is discharged
from the air handling unit. Plenum boxes may also be used on the return side of the unit in lieu of a
mixing box. Air-flow control dampers shall be mounted on the ductwork connecting to the plenum box.
Mixing Boxes:

Air-handling units shall be provided with mixing boxes where relief air is discharged from the air
handling unit Mixing boxes may also be used on the return side of the unit in lieu of a plenum box. Air
flowcontrol dampers shall be mounted within the mixing box or on the ductwork connecting to
Terminals. the mixing box.

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AIR DELIVERY DEVICES
Terminal ceiling diffusers or booted-plenum slots should be specifically designed for VAV air distribu-
tion. Booted plenum slots should not exceed 1.2 meters (4 feet) in length unless more than one source of
supply is provided. “Dumping” action at reduced air volume and sound power levels at maximum m3/s
(cfm) delivery should be minimized. For VAV systems, the diffuser spacing selection should not be based
on the maximum or design air volumes but rather on the air volume range where the system is expected
to operate most of the time. The designer should consider the expected variation in range in the outlet air
volume to ensure the air diffusion performance index (ADPI) values remain above a specified minimum.
This is achieved by low temperature variation, good air mixing, and no objectionable drafts in the
occupied space, typically 150 mm (6 inch) to 1830 mm (6 feet) above the floor. Adequate ventilation
requiresthat the selected diffusers effectively mix the total air in the room with the supplied conditioned
air, whichis assumed to contain adequate ventilation air.

TERMINALS
All motors shall have premium efficiency as per ASHRAE 90.1. 1/2 HP and larger shall be polyphase.
Motors smaller than 1/2 HP shall be single phase. For motors operated with variable speed drives, provide
insulation cooling characteristics as per NEC and NFPA.

BOILERS
Boilers for hydronic hot water heating applications shall be low pressure, with a working pressure and
maximum temperature limitation as previously stated, and shall be installed in a dedicated mechanical
room with all provisions made for breeching, flue stack and combustion air. For northern climates, a
minimum of three equally sized units shall be provided. Each of the three units shall have equal capaci-
ties such that the combined capacity of the three boilers shall satisfy 120 percent of the total peak load of
heating and humidification requirements. For southern climates, a minimum of two equally sized units at
67 percent of the peak capacity (each) shall be provided. The units shall be packaged, with all components
and controls factory preassembled. Controls and relief valves to limit pressure and temperature must
be specified separately. Burner control shall be return water temperature actuated and control
sequences, such as modulating burner control and outside air reset, shall be utilized to maximum
efficiency and performance.multiple closet type condensing boilers shall be utilized, if possible. Boilers
shall haveself-contained microprocessor controls capable of connecting to and interoperating with a
BACnet or
LONWORKS Direct Digital Control (DDC) Building Automated System. Boilers shall have a minimum
efficiency of 80 percent as per ASHRAE 90.1.
Individual boilers with ratings higher than 29 MW (100 million Btu/hour) or boiler plants with ratings
higher than 75 MW (250 million Btu/hour) are subject to review by the Environmental Protection
Agency.
Boilers shall be piped to a common heating water header with provisions to sequence boilers on-line to
match the load requirements. All units shall have adequate valving to provide isolation of off-line units
without interruption of service. All required auxiliaries for the boiler systems shall be provided with
expansion tanks, heat exchangers, water treatment and air separators, as required.

Gas Trains: Boiler gas trains shall be in accordance with International Risk Insurance (IRI) standards.

Automatic Valve Actuators: Gas valve actuators shall not contain NaK (sodium-potassium) elements since
these pose a danger to maintenance personnel
Gas Trains: Boiler gas trains shall be in accordance with International Risk Insurance (IRI) standards.

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Automatic Valve Actuators:

Gas valve actuators shall not contain NaK (sodium-potassium) elements since these pose a danger to
maintenance personnel.

Venting:

Products of combustion from fuel-fired appliances and equipment shall be delivered outside of the
building through the use of breeching, vent, stack and chimney systems. Breeching connecting fuel-fired
equipment to vents, stacks and chimneys shall generally be horizontal and shall comply with NFPA 54.
Vents, stacks and chimneys shall generally be vertical and shall comply with NFPA 54 and 211. Breeching,
vent, stack, and chimney systems may operate under negative, neutral, or positive pressure and shallbe
designed relative to the flue gas temperature and dew point, length and configuration of the system, and
the value of the insulation techniques applied to the vent. Venting materials may be factory fabricaed and
assembled in the field and may be double or single wall systems depending on the distance from adjacent
combustible or non-combustible materials. Material types, ratings and distances to adjacent building
materials shall comply with NFPA 54 and 211.

HEAT EXCHANGER
Steam-to-water heat exchangers shall be used in situations where district steam is supplied and a hot
water space heating and domestic hot water heating system have been selected. Double-wall heat ex-
changers shall be used in domestic hot water heating applications. Plate heat exchangers shall be used
for waterside economizer applications.

CHILLERS
Chillers shall be specified in accordance with the latest Air-conditioning and Refrigeration Institute
(ARI) ratings procedures and latest edition of the ASHRAE Standard 90.1. As a part of the life cycle cost
analysis, the use of high-efficiency chillers with COP and IPLV ratings that exceed 6.4 (0.55 kW/ton)
should be analyzed. Likewise, the feasibility of gas-engine driven chillers, ice storage chillers, and ab-
sorption chillers should be considered for demand shedding and thermal balancing of the total system.

BACnet or LONWORKS Microprocessor-based controls shall be used. The control panel shall have
self-diagnostic capability, integral safety control and set point display, such as run time, operating
parameters, electrical low voltage and loss of phase protection, current and demand limiting, and
output/input-COP [input/output (kW/ton)] information.

Chilled water machines:

When the peak cooling load is 1760 kw (500 tons) or more, a minimum of three chilled water machines
shall be provided. The three units shall have a combined capacity of 120 percent of the total peak cooling
load with load split percentages 40-40-40 or 50-50-20. If the peak cooling load is less than 1760 kW (500
tons), a minimum of two equally sized machines at 67 percent of the peak capacity (each) shall be pro-
vided. All units shall have adequate valving to provide isolation of the off-line unit without interruption
of service. Cooling systems with a capacity less than 50 tons shall use air cooled chillers.
Chillers shall be piped to a common chilled water header with provisions to sequence chillers on-line
to match the load requirements. All required auxiliaries for the chiller systems shall be provided with
expansion tanks, heat exchangers, water treatment and air separators, as required. If multiple chillers are
used, automatic shutoff valves shall be provided for each chiller.

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Chiller condenser bundles shall be equipped with automatic reversing brush-type tube cleaning systems.
Chiller condenser piping shall be equipped with recirculation/bypass control valves to maintain incoming
condenser water temperature within chiller manufacturer’s minimum. Part load efficiency must be
specified in accordance with ARI Standard 550/590.
The design of refrigeration machines must comply with Clean Air Act amendment Title VI: Stratospheric
Ozone Protection and Code of Federal Regulations (CFR) 40, Part 82: Protection of Stratospheric Ozone.
Chlorofluorocarbon (CFC) refrigerants are not permitted in new chillers. Acceptable non-CFC refrigerants
are listed in EPA regulations implementing Section 612 (Significant New Alternatives Policy (SNAP) of the
Clean Air Act, Title VI: Stratospheric Ozone Protection. (Note: GSA accepts these criteria in documenting
certification of LEED ratings. )
Refrigeration machines must be equipped with isolation valves, fittings and service apertures as
appropriate for refrigerant recovery during servicing and repair, as required by Section 608 of the Clean
Air Act, Title VI. Chillers must also be easily accessible for internal inspections and cleaning

COOLING TOWERS
Multiple cell towers and isolated basins are required to facilitate operations, maintenance and redundancy.
The number of cells shall match the number of chillers. Supply piping shall be connected to a manifold to
allow for any combination of equipment use. Multiple towers shall have equalization piping between cell
basins. Equalization piping shall include isolation valves and automatic shutoff valves between each cell.
Cooling towers shall have ladders and platforms for ease of inspections and replacement of components.
Variable speed pumps for multiple cooling towers shall not operate below 30 percent of rated capacity.
Induced draft cooling towers with multiple-speed or variable-speed condenser fan controls shall be
considered. Induced draft towers shall have a clear distance equal to the height of the tower on the air
intake side(s) to keep the air velocity low. Consideration shall be given to piping arrangement and strainer
or filterplacement such that accumulated solids are readily removed from the system. Clean-outs for
sediment removal and flushing from basin and piping shall be provided.
Forced draft towers shall have inlet screens. Forced draft towers shall have directional discharge plenums
where required for space or directional considerations. Consideration shall be given to piping arrangement
and strainer or filter placement such that accumulated solids are readily removed from the system. Clean-
outs for sediment removal and flushing from basin and piping shall be provided. The cooling tower’s
foundation, structural elements and connections shall be designed for a 44 m/s (100 MPH) wind design
load.
Cooling tower basins and housing shall be constructed of stainless steel. If the cooling tower is located on
the building structure, vibration and sound isolation must be provided. Cooling towers shall be elevated to
maintain required net positive suction head on condenser water pumps and to provide a 4-foot minimum
clear space beneath the bottom of the lowest structural member, piping or sump, to allow reroofing beneath
the tower.
Special consideration should be given to de-icing cooling tower fills if they are to operate in sub-freezing
weather, such as chilled water systems designed with a water-side economizer. A manual shutdown for the
fan shall be provided. If cooling towers operate intermittently during sub-freezing weather, provisions shall
be made for draining all piping during periods of shutdown. For this purpose indoor drain down basins
are preferred to heated wet basins at the cooling tower. Cooling towers with waterside economizers and
designed for year-round operation shall be equipped with basin heaters. Condenser water piping located
above-grade and down to 3 feet below grade shall have heat tracing. Cooling towers shall be provided with
BACnet LON WORKS microprocessor controls, capable of connecting to central building automation
systems.

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 HEATING SYSTEMS
STEAM HEATING
District steam heating, if available, shall be used if determined to be economical and reliable through a life
cycle cost analysis. If steam is furnished to the building, such as under a district heating plan, it should be
converted to hot water with a heat exchanger in the mechanical room near the entrance into the building.
If steam heating is used, the designer shall investigate the use of district steam condensate for pre-heating
of domestic hot water. Steam heating is not permitted inside the building other than conversion of steam-
to-hot water in the mechanical room.
Also, the use of steam for HVAC applications shall be limited to the conversion of steam heat to hot water
heat and for use in providing humidification. Steam shall not be used as a heating medium for distribution
throughout a building to terminal units, air handling units, perimeter heating units, coils, or any other
form of heat transfer where steam is converted to a source of heat for use in space comfort control or
environmental temperature control.
Steam delivered from any source other than a clean steam generation system shall be prohibited from use
in providing humidification. Steam delivered from a central plant, a district steam system, steam boilers, or
any equipment where chemicals are delivered into the medium resulting in the final product of steam shall
not be used for the purpose of providing humidification to the HVAC system or occupied spaces.

HOT WATER HEATING SYSTEMS

GSA prefers low-temperature hot-water heating systems; 205 kPa (30 psi) working pressure and maximum
temperature limitation of 93.3°C (200°F). The use of electric resistance and/or electric boilers as the prima-
ry heating source for the building is prohibited. Design and layout of hydronic heating systems shall
followthe principles outlined in the latest edition of the ASHRAE Systems and Equipment Handbook.

Temperature and Pressure Drop.

Supply temperatures and the corresponding temperature drops for space heating hot water systems must
be set to best suit the equipment being served. Total system temperature drop should not exceed 22°C
(72°F). The temperature drop for terminal unit heating coils shall be 11°C (52°F). Design water velocity in
piping should not exceed 2.5 meters per second (8 feet per second) or design pressure friction loss in
piping systems should not exceed 0.4 kPa per meter (4 feet per 100 feet), whichever is larger, and not less
than
1.3 meters per second (4 feet per second).

Freeze Protection.
Propylene glycol manufactured specifically for HVAC systems shall be used to protect hot water systems
from freezing, where extensive runs of piping are exposed to weather, where heating operations are
intermittent or where coils are exposed to large volumes of outside air. Freeze protection circulation pump
shall be provided along with polypropylene glycol. Heat tracing systems are not acceptable for systems
inside the building. Glycol solutions shall not be used directly in boilers, because of corrosion caused by
the chemical breakdown of the glycol. The water make-up line for glycol systems shall be provided with an
in-line water meter to monitor and maintain the proper percentage of glycol in the system. Provisions shall
be made for drain down, storage and re-injection of the glycol into the system.

Radiant Heat. Radiant heating systems (hot water or gas fired) may be overhead or under floor type. They
should be considered in lieu of convective or all-air heating systems in areas that experience infiltration
loads in excess of two air changes per hour at design heating conditions. Radiant heating systems may also
be considered for high bay spaces and loading docks.

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Heat recovery systems are utilized in all ventilation units (100 percent outside air units) and where the
temperature differentials between supply air and exhaust air is significant. Heat recovery should operate
at a minimum of 70 percent efficiency. The heat recovery systems must be capable of connecting to a
micro processor controller that in turn can be connected to a direct digital control (DDC) Building
Automation System. Profilers shall be provided in all heat recovery systems before the heat recovery
equipment.

Heat Pipe.

For sensible heat recovery a run around type heat pipe shall use refrigerant to absorb heat from the air
stream at the air intake and reject the heat back into the air stream at the discharge of the air-handling
unit. System shall have solenoid valve control to operate under partial load conditions.

Run-around Coil.

A glycol run-around coil could be used with control valves and a pump for part load conditions. The run-
around coils shall be used at the exhaust discharge from the building and at the fresh air intake into the
building. The run-around coil system shall be capable of connecting to a microprocessor controller that in
turn can be connected to a DDC Building Automation system.

Enthalpy Wheel.

A desiccant-impregnated enthalpy wheel with variable speed rotary wheel may be used in the supply and
exhaust systems.

Sensible Heat Recovery.

For sensible heat recovery, a cross-flow, air-to-air (z-duct) heat exchanger shall recover the heat in the
exhaust and supply air streams. Z-ducts shall be constructed entirely of sheet metal. Heat-wheels may also
be used for sensible heat recovery. Unit shall have variable speed drive for controlling the temperature
leaving the unit

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 COOLING SYSTEMS
CHILLED WATER SYSTEMS
Chilled water systems include chillers, chilled water and condenser water pumps, cooling towers, piping
and piping specialties.
The chilled water systems shall have a 10°C (50°F) temperature differential in the central system, at the
central plant, with a design supply water temperature between 4°C and 7°C (40°F and 45°F). In climates
with low relative humidity, an 8°C (46°F) may be used. The chilled water system shall have a 6°C (43°F)
temperature differential in the secondary systems, at the terminal points of use, such as coils with a design
supply water temperature between 4°C and 7°C (40°F and 45°F).
District chilled water, if available, shall be used for cooling only if determined to be economical and reli-
able through a life cycle cost analysis.

Freeze Protection.
Propylene glycol manufactured specifically for HVAC Systems is used for freeze protection, primarily in
low temperature chilled water systems (less than 4°C) (less than 40°F). The concentration of antifreeze
should be kept to a practical minimum because of its adverse effect on heat exchange efficiency and pump
life. The water make-up line for glycol systems shall be provided with an in-line water meter to monitor
and maintain the proper percentage of glycol in the system. All coils exposed to outside airflow (at some
time) shall be provided with freeze protection thermostats and control cycles. Provisions shall be made for
drain down, storage and re-injection of the glycol into the system.

Condenser Water.
All water-cooled condensers must be connected to a re-circulating heat-rejecting loop. The heat rejection
loop system shall be designed for a 6°C (43°F) temperature differential and a minimum of 4°C (40°F) wet
bulb approach between the outside air temperature and the temperature of the water leaving the heat
rejection equipment. Heat tracing shall be provided for piping exposed to weather and for piping down to 3
feetbelow grade.

SPECIAL COOLING SYSTEMS

Waterside Economizer Cycle.
In certain climate conditions cooling towers are capable of producing condenser water cold enough to
cool the chilled water system without chiller operation. This option shall be considered in life cycle cost
comparisons of water cooled chillers. Waterside economizer cycles are particularly cost effective in the
low humidity climates of the western United States. In the eastern United States, enthalpy airside econo-
mizer cycles tend to produce lower operating costs. However, where used, any airside economizer shall be
set so that no air with a dew point above 10°C (50°F) is allowed into the building. Waterside economizer
systems shall be used only in areas where the outside air temperature will be below 4.4°C (40°F) wet bulb.
Waterside economizers shall utilize a plate heat exchanger piped in parallel arrangement with its respective
chiller.

Desiccant Cooling. For high occupancy applications where moisture removal is required, solid desiccant
with silica gel may be used in combination with mechanical cooling. Heat recovery wheels may be used
prior to the mechanical cooling process. Desiccant cooling units shall be equipped with airflow-setting
devices for both process and reactivation air flows, and shall be equipped with gauges or digital displays to
report those air flows continuously. The desiccant cooling system shall have self-contained microprocessor
controls capable of connecting to and interoperating with a direct digital control (DDC) Building
Automation system. Natural gas or condenser waste heat shall be used as fuel for reactivation of the
desiccant.Lithium chloride liquid desiccants are not permitted.

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 HUMIDIFICATION AND WATER
TREATMENT

HUMIDIFIERS AND DIRECT OPERATIVE COOLERS

Make-up water for direct evaporation humidifiers and direct evaporative coolers, or other water spray
systems shall originate directly from a potable source that has equal or better water quality with respect to
both chemical and microbial contaminants. Humidifiers shall be designed so that microbicide chemicals
and water treatment additives are not emitted in ventilation air. All components of humidification equip-
ment shall be stainless steel. Air washer systems are not permitted for cooling.
Humidification should be limited to building areas requiring special conditions. Courtrooms with wall
coverings of wood should be provided with humidification. General office space shall not be humidified
unless severe winter conditions are likely to cause indoor relative humidity to fall below 30 percent. Where
humidification is necessary, atomized hot water, clean steam or ultrasound may be used and shall be
generated by electronic or steam-to-steam generators. To avoid the potential for over saturation and
condensation at low load, the total humidification load should be divided between multiple,
independently-modulated units. Single-unit humidifiers are not acceptable. When steam is required during
summer seasons for humidification or sterilization, a separate clean steam generator shall be provided and
sized for the seasonal load. Humidifiers shall be cantered on the air stream to prevent stratification of the
moist air. All associated equipment and piping shall be stainless steel. Humidification system shall have
microprocessorcontrols and the capability to connect to building automation systems.

WATER TREATMENT
The water treatment for all hydronic systems, including humidification systems, shall be designed by a
qualified specialist. The design system shall address the three aspects of water treatment: biological growth,
dissolved solids and scaling, and corrosion protection. The performance of the water treatment systems
shall produce, as a minimum, the following characteristics; hardness: 0.00; iron content: 0.00; dissolved
solids: 1,500 to 1,750 ppm; silica: 610 ppm or less; and a PH of 10.5 or above. The system shall operate with
an injection pump transferring chemicals from solution tank(s) as required to maintain the conditions
described. The chemical feed system shall have self-contained microprocessor controls capable of
connecting to and interoperating with a Direct Digital Control (DDC) Building Automation System. The
methodsused to treat the systems’ make-up water shall have prior success in existing facilities on the same
municipal water supply

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VARIABLE AIR VOLUME SYSTEMS
The VAV supply fan shall be designed for the largest block load, not the sum of the individual peaks. The
air distribution system up to the VAV boxes shall be medium pressure and shall be designed by using the
static regain method. Downstream of the VAV boxes the system shall be low and medium pressure
construction and shall be designed using the equal friction method. Sound lining is not permitted. Double
wall ductwork with insulation in-between is permitted in lieu of sound lining. All VAV boxes shall be
accessible for maintenance. Ducted return shall be utilized at all locations. VAV fan-powered box supply
andreturn ducts shall have double wall ductwork with insulation in-between for a minimum distance of 5
feet.

UNDER FLOOR AIR DISTRIBUTION SYSTEMS

Provide plenum zones both for perimeter and interior in order to control the under floor variable volume
dampers or boxes with separate plenum barriers between perimeter and interior zones. The under floor
plenum shall be air tight and compartmentalized with baffles. Provisions shall be provided for cleaning the
plenum space. When under floor supply air distribution is used, the ceiling plenum shall be used for the
distribution of the ducted return air. The perimeter and interior under floor zones shall be clearly
separated in order to maintain proper pressurization, temperature and humidity control. Zoning of the
under- floor air distribution systems shall be in accordance with descriptions presented elsewhere in this
chapter.Perimeter wall below the raised flooring system shall be provided with R-30 insulation and vapor
barrier below the raised floor. All VAV boxes that are part of an under floor air distribution system for
both perimeter and interior systems shall be located below the raised floor. The floor area used for an
under floor system shall have the slab provided with a minimum of R-10 insulation and vapor barrier from
below.
This shall incorporate the entire slab area used for the under floor system.

VOLUME CONTROL
Particular attention shall be given to the volume control. VAV systems depend on air volume modulation
to maintain the required ventilation rates and temperature set points. Terminal air volume control devices
are critical to the successful operation of the system and shall be provided. Zone loads must be calculated
accurately to avoid excessive throttling of air flow due to oversized fans and terminal units. Diffusers shall
be high entrainment type (3:1 minimum) to maximize air velocity at low flow rates. If ventilation air is
delivered through the VAV box, the minimum volume setting of the VAV box should equal the larger of
the following:

1. 30 percent of the peak supply volume;

2. 0.002 m3/s per m2 (0.4 cfm/sf) of conditioned zone area; or
3. Minimum m3/s (cfm)to satisfy Standard 62 ventilation requirements. VAV terminal units must never be
shut down to zero when the system is operating. Outside air requirements shall be maintained in
accordance with the Multiple Spaces Method.

Airside Economizer Cycle.

An air-side enthalpy economizer cycle reduces cooling costs when outdoor air enthalpy is below a preset
high temperature limit, usually 15 to 21°C (60°F to 70°F), depending on the humidity of the outside air.
Airside economizers shall only be used when they can deliver air conditions leaving the air handling unit
of a maximum of 10°C (50°F) dew point and a maximum of 70 percent relative humidity. Enthalpy
economizers shall operate only when return air enthalpy is greater than the outside air enthalpy.
All air distributions systems with a capacity greater than 1,416 LPS (3,000 CFM) shall have an air-side
economizer.

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 DUCTWORK SUPPLY & RETURN
Ductwork Pressure

Following table provides pressure classification and maximum air velocities for all ductwork. Ductwork
construction shall be tested for leakage prior to installation. Each section tested must have a minimum of
a 20 ft. length straight-run, a minimum of two elbows and a connection to the terminal. The stated static
pressures represent the pressure exerted on the duct system and not the total static pressure developed by
the supply fan. The actual design air velocity should consider the recommended duct velocities in Table 5-4
when noise generation is a controlling factor. Primary air ductwork (fan connections, risers, main
distribution ducts) shall be medium pressure classification as a minimum. Secondary air ductwork (run
outs/ branches from main to terminal boxes and distribution devices) shall be low pressure classification as
a minimum.
Supply, return and exhaust air ducts shall be designed and constructed to allow no more than 3 percent
leakage of total airflow in systems up to 750 Pa (3 inches WG). In systems from 751 Pa (3.1 inches WG)
through 2500 Pa (10.0 inches WG) ducts shall be designed and constructed to limit leakage to 0.5 percent
of the total air flow.
Pressure loss in ductwork shall be designed to comply with the criteria stated above. This can be
accomplished by using smooth transitions and elbows with a radius of at least 1.5 times the radius of the
duct. Where mitered elbows have to be used, double foil sound attenuating turning vanes shall be
provided. Mitered elbows are not permitted where duct velocity exceeds 10m/s (2000 FPM).

STATIC PRESSURE AIR VELOCITY DUCT CLASS

250 Pa (1.0 in W.G.) < 10 m/s DN < (2000 FPM DN) Low Pressure
500 Pa (2.0 in W.G) < 10 m/s DN < (2000 FPM DN) Low Pressure
750 Pa (3.0 in W.G.) < 12.5 m/s DN < (2500 FPM DN) Medium Pressure
1000 Pa (+4.0 in W.G.) < 10 m/s DN > (2000 FPM UP) Medium Pressure
1500 Pa (+6.0 in W.G.) < 10 m/s DN > (2000 FPM UP) Medium Pressure
2500 Pa (+10.0 in W.G.) < 10 m/s DN > (2000 FPM UP) High Pressure

CONTROLLING FACTOR NOISE GENERATION

APPLICATION
(MAIN DUCT VELOCITIES)

m/s (fpm)

Private Offices 6 (1,200)

Conference Rooms
Libraries

Theaters 4 (800)
Auditoriums

General Offices 7.5 (1,500)

Cafeterias 9 (1,800)

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Sizing of Ductwork. Supply and return ductwork shall be sized using the equal friction method except for
ductwork upstream of VAV boxes. Duct systems designed using the equal friction method place enough
static pressure capacity in the supply and return fans to compensate for improper field installation and
changes made to the system layout in the future. In buildings with large areas of open plan space, the
main duct size shall be increased for revisions in the future. Air flow diversity shall also be a sizing
criterion. 80 percent diversity can be taken at the air-handling unit and decreased the farther the
ductwork is from the source until air flow diversity is reduced to zero for the final portion of the system.

Ductwork Construction. Ductwork shall be fabricated from galvanized steel, aluminum or stainless steel
sheet metal depending on applications. Flex duct may be used for low pressure ductwork downstream of
the terminal box in office spaces. The length of the flex duct shall not exceed the distance between the low
pressure supply air duct and the diffuser plus 20 percent to permit relocation of diffusers in the future
while minimizing replacement or modification of the hard ductwork distribution system. Generally, flex
duct runs should not exceed 3 m (10 feet) nor contain more than two bends.
Joint sealing tape for all connections shall be of reinforced fiberglass backed material with field applied
mastic. Use of pressure sensitive tape is not permitted.

Ceiling Plenum Supply.

Ceiling plenum supply does not permit adequate control of supply air and should avoid to use.

Raised Floor Plenum Supply.

In computer rooms, under floor plenum supplies are appropriate. As a general application in other
areas(e.g. open offices), under floor air distribution/displacement systems are appropriate. Where
raised floorplenums are used for supply air distribution, the plenums shall be properly sealed to
minimize leakage.R-30 insulation with vapor barrier shall be provided for perimeter of raised floor
walls.

Plenum and Ducted Returns.

With a return plenum care must be taken to ensure that the air drawn through the most remote register
actually reaches the air-handling unit. The horizontal distance from the farthest point in the plenum to a
return duct shall not exceed 15 m (50 feet). No more than 0.8 m3/s (2,000 cfm) should be collected at any
one return grille. Figure 5-2 illustrates an example of an open ceiling plenum with return air ductwork.
Return air plenums should be avoided. When deemed necessary for economic reasons, plenums shall be
sealed air-tight with respect to the exterior wall and roof slab or ceiling deck to avoid creating negative air
pressure in exterior wall cavities that would allow intrusion of untreated outdoor air. All central multi-
floor-type return air risers must be ducted.
Other less flexible building spaces, such as permanent circulation, public spaces, and support spaces,
shall have ducted returns. Where fully ducted return systems are used, consider placing returns low in
walls or on columns to complement ceiling supply air.
Return air duct in the ceiling plenum of the floor below the roof shall be insulated. Double wall ductwork
with insulation in-between shall be used in lieu of sound lining for a minimum of the last 5 feet before
connecting to the air handling unit or a return air duct riser.
Ceiling Return Plenum with
Minimal Return Ductwork

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 PIPING SYSTEMS

CHILLED WATER AND CONDENSERS WATER PIPING

In general, HVAC systems shall utilize parallel piping systems with a two-pipe main distribution system
arranged in a reverse return configuration. If applied, series loop piping for terminal or branch circuits
shall be equipped with automatic flow control valves at terminal units (all types of heat transfer units).

Each terminal unit or coil shall be provided with isolation valves on both the supply and return and a
flow indicating balance valve on the return line. Isolation valves shall be provided on all major branches,
such as at each floor level, building wing or mechanical room.
For new chilled water HVAC distribution, a pumping and piping arrangement is generally appropriate,
with constant volume primary pumping and variable volume secondary pumping. The primary and
secondary circuits shall be separate, with neither having an effect on the pumping head of the other. The
primary circuit serves the source equipment (chillers), while the secondary circuit serves the load. Refer
also to Pumping Systems in this chapter for additional requirements.

This procedure is to define the method used to ensure that the Chilled Water Pipe work System
comprising all pipes, tubes, valves, fittings, reducers, expanders, nipples, vents, bleed off, expansion and
contraction devices, hangers, brackets, anchors, supports, sleeves, plates and all accessories and
components connected thereto as an integrated pipe work system, installation final connections and
workmanship, iscorrect and acceptable and conforms to the contract documents and General
Specifications.

Isolation of Piping at Equipment.

Isolation valves, shutoff valves, by-pass circuits, flanges and unions shall be provided as necessary for
piping at equipment to facilitate equipment repair and replacement. Equipment requiring isolation
includes boilers, chillers, pumps, coils, terminal units and heat exchangers. Valves shall also be provided
for zones off vertical risers.

Piping Supports.
Provide channel supports for multiple pipes and heavy duty steel trapezes to support multiple pipes.
Hanger and support schedule shall have manufacturer’s number, type and location. Comply with MSS
SP69 for pipe hanger selections. Spring hangers and supports shall be provided in all the mechanical
rooms.

Flexible Pipe Connectors.

Flexible pipe connectors shall be fabricated from annular close pitched corrugated and braided stainless
steel. All pumps, chillers, and cooling towers shall have flexible connectors.

Piping System and Equipment Identification.

All pipes, valves and equipment in mechanical rooms, shafts, ceilings and other spaces accessible to
maintenance personnel must be identified with color-coded bands and permanent tags indicating the
system type and direction of flow for piping systems or type and number for equipment. The
identification system shall also tag all valves and other operable fittings. Gas piping and sprinkler lines
must be identified as prescribed by related authorities.

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STANDARDS FOR PIPING MATERIAL

Standards for Piping Material

Standard Piping Material Use Comments

ASTM Schedule 40 Chilled water up to 300 1035 kPa (150 psi) fittings.
mm (12-in) dia., Standard weight pipe over 300 mm (12-in)
Condenser water up to diameter.
300 mm (12-in) dia.
Test to 2100 kPa (300 psig)
Hot water
Weld and test to 2100 kPa (300 psig)
Natural gas, fuel oil

Steam (100 kPa (15 psig)

to 1035 kPa (150 psi))

ASTM Schedule 30 Chilled water over 300 1035 kPa (150 psi) fittings.
mm (12 in) dia Standard weight pipe over 300 mm (12-in)
Condenser water over 300 diameter
mm (12 in) dia.

ASTM Schedule 80 Steam condensate

Copper Tubing Chilled water up to 102 Builder’s option. Use type K below ground
mm (4 in) dia, and type L above.
Condenser water up to
102 mm (4 in) dia. Lead-free solder connections.
Type ACR.
Domestic water
Refrigeration
Cast Iron Sanitary, waste
and vent
Storm

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EXPANSION TANK
The expansion tank should be connected on the inlet side of the circulating pump.
It is a good idea to install a service valve at the expansion tank to facilitate future maintenance. However,
the valve handle should be removed to prevent the tank from being isolated from the main loop.
The tank will function properly in any position, but it must not stress the connection to the supporting
pipe. Thus, the tank should usually be mounted vertically. Do not install the expansion tank (and its ser-
vice valve) in such a way that its weight is a big lever that stresses the pipe connection or pipe.

VFD - VARIABLE FREQUENCY DRIVE

Frequency drives are also known as VFDs, variable frequency drives, VSDs, variable speed drives, and
sometimes just "drives". Frequency drives are used primarily to eliminate the sudden current inrush that
can cause lights to flicker when a compressor turns on. Frequency drives can also be used to convert
single-phase power to 3-phase.

The chiller must have a 3-phase compressor, but the VFD can use either 1- or 3-phase input power. The
control panel should match the ship's power, whether 1 or 3 phase. Power wiring typically goes from the
control panel to the VFD, and from the VFD to the compressor. The VFD functions as the contactor/starter.
The control box typically provides a dry contact for the VFD to control when the VFD turns on/off.

PUMP INSTALLATION
Pump Installation Procedure Before starting the pump installation process mechanical or AC engineer
to study the pump manufacturer’s written installation and alignment instructions. A layout drawing
should be approved and pumps should be installed in locations indicated making sure that there is
sufficient access space for periodic maintenance, removal of motors impellers, couplings and
accessories. Setbase-mounted pumps on concrete equipment bases as indicated on drawings. Suitable
lifting equipment
should be used to lift and place the pumps on its location. Disconnect couplings to the half before setting.
Do not reconnect couplings until alignment operations have been completed. Install suction and discharge
pipe sizes equal to or greater than the diameter of water pump connections. Install valves of types and at
locations indicated that are same size as the piping connecting chilled water pump, bypasses, test headers
and other piping systems. Install pressure gages on chilled water pump suction and discharge in such way
to be easily readable and completely isolated from vibration.
Support pumps and piping separately so that weight of piping system does not rest on pumps or its sup-
port. Install piping accessories, hangers and supports, anchors, valves meters and gages, and equipment
support as indicated for complete installation. Electrical Wiring: Install electrical devices furnished by
equipment manufacturers but not specified as factory mounted. Furnish copy of manufacturers wiring
diagram for submittal to the Consultant. Verify that electrical wiring is installed according to manufacturer’s
recommendations and installation requirements. Work to be inspected and approved by consultant and do
not proceed with equipment start up until wiring installation is acceptable.
Chilled Water Pump Alignment Align pump and driver shafts after complete unit has been leveled on
foundation and after grout has set and foundation bolts have been tightened. After alignment is correct,
tighten foundation bolts evenly but not too firmly. Fill base plate completely with non-shrink, non-metallic
grout, with metal blocks and shims or wedges in place. After grout has hardened, fully tighten foundation
bolts. Check alignment and take corrective measures required to ensure perfect alignment. Make piping
connections and check alignment again, and take corrective measures if required. Connect flow-measuring
and other hydraulic system components according to manufacturer’s written installation instructions

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85
957
85
5
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 INSULATION
AKHWAN always uses materials which are comply with the fire and smoke hazard ratings indicated
by ASTM-E84, NFPA 255 and UL 723. Accessories such as adhesives, mastics, cements and tapes shall
havethe same or better fire and smoke hazard ratings.
Special care take in application of insulation e.g Insulation application on all cold surface mechanical
systems, such as ductwork and piping, where condensation has the potential of forming and in accordance
with Standard.

DUCT INSULATION

Materials used as internal insulation exposed to the air stream in ducts shall be in accordance with UL 181or ASTM C 1071
erosion tests, and shall not promote or support the growth of fungi or bacteria, in accordance with UL 181 and ASTM G21
and G22. Ductwork with double wall construction having insulation in-between shall only be used for courtroom return air
transfer grilles, and only if required for acoustic purposes. All exposed ductwork shall have sealed canvas jacketing. All
concealed ductwork shall have foil face jacketing.

All the insulations are comply with fire and smoke hazard ratings indicated by ASTM-E84, NFPA 255 and
UL 723. Accessories such as adhesives, mastics, cements, tapes, etc. shall have the same or better
component ratings. All supply air ducts always insulated, in accordance with Standard 90.1.

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Protect Supply air duct insulation with vapor barrier jacket. The insulation cover the duct system with a
continuous, unbroken vapor seal. Insulation shall have zero permeability.

Return air and exhaust air distribution systems always insulated in accordance with the Standard set
standards.
Always evaluate insulation of return air and exhaust air distribution systems or each project and for each
system to guard against condensation formation and heat gain/loss on a re-circulating or heat recovery
system. Generally, return air and exhaust air distribution systems do not require insulation if located in a
ceiling plenum or mechanical room used as a return air plenum.

PIPING INSULATION
All of our insulation materials are comply with the fire and smoke hazard ratings indicated by ASTM-E84,
NFPA 255 and UL 723. Accessories such as adhesives, mastics, cements, tapes, etc. shall have the same or
better component ratings. Piping systems conveying fluids, those having design temperatures less than
18°C (65°F) or greater than 40°C (105°F) shall be insulated. All piping systems with surface temperatures
below the average dew point temperature of the indoor ambient air and where condensate drip will cause
damage or create a hazard shall be insulated with a vapor barrier to prevent condensation formation
regardless to whether piping is concealed or exposed. Chilled water piping systems shall be insulated with
nopermeable insulation (of perm rating 0.00) such as cellular glass. All exposed and concealed piping
shall have PVC jacketing.

All insulation material shall comply with the fire and smoke hazard ratings indicated by ASTM-E84, NFPA
255 and UL 723. Accessories such as adhesives, mastics, cements, tapes, etc. shall have the same or better
component ratings. All equipment including air handling units, chilled and hot water pumps, and heat
exchangers must be insulated in accordance with Standard 90.1. All pumps shall have jacketing

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 METERS, GAUGES AND FLOW
MEASURING DEVICES

THERMOMETERS AND GAUGES.

Each piece of our mechanical equipment is provided with the instrumentation or test ports to verify
critical parameters, such as capacity, pressures, temperatures, and flow rates. Following are the general
instrumentation requirements:

Thermometers and pressure gauges are used for the suction and discharge of all pumps, chillers, boilers,
heat exchangers, cooling coils, heating coils, and cooling towers. To avoid pressure gauge tolerance errors,
a single pressure gauge may be installed, valve to sense both supply and return conditions. For coils with
less than 10 gpm flow, provisions for use of portable instruments to check temperatures and pressures.

Duct static pressure gauges are used to provided for the central air-handling unit air supply fan discharge,
branch take-offs of vertical supply risers and at all duct locations at which static pressure readings are
being monitored to control the operation of a VAV system.

Differential static pressure gauges are always be placed across filters in air-handling units and to measure
building pressure relative to the outdoors. A temperature gauge is required at the outside air intake to each
air-handling unit.

Flow Measuring Devices. Airflow measuring grids are required for all central air-handling units.
Measuring grids to be provided at the supply air duct, return air duct, and the outside air duct. Airflow
measuringgrids must be sized to give accurate readings at minimum flow. It may be necessary to reduce
the duct sizeat the station to permit accurate measurement.

Water flow or energy measuring devices are required for each chilled water refrigeration machine, hot
water boiler, pump, and connections to district energy plants. Individual water flow or energy measuring
devices are provided for chilled water lines serving computer rooms and chilled water and hot water lines
to out leased spaces. Our flow measuring devices are capable of communicating with the central BAS.
Testing Stations. Permanent or temporary testing stations always provided for start up and testing of
building systems. Connections shall be designed so temporary testing equipment can be installed and
removed without shutting down the system.

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 MINIMUM CONTROL & MONITORING
POINTS FOR TYPICAL HVAC
EQUIPMENT

Central Air Handling Units Refrigeration Equipment Hot Water Boilers

Start/Stop Start/Stop
Heating Control Leave Water Temp Reset Start/Stop
Cooling Control Demand Limiting
Leaving Water Temp Reset
Humidification Control Isolation Valve Position
Supply Air Reset Leaving Water Temp Reset Isolation Valve Position
Static Pressure Reset Entering Water Temp
Leaving Water Temp
Building and Zone kW Draw
Pressurization Control Flow Entering Water Temp
Damper Position (economizer) Return Air Flow Rate
Flow
Supply Air Discharge Temp
Return Air Temp BTU Draw
Mixed Air Temp
Supply Air Flow Rate
Filter Differential Pressure
Air Flow Measuring Station

Cooling Towers Terminal Boxes Pumps

Start/Stop Start/Stop Start/Stop

Leaving Water Temp Reset Discharge Temp Reset Discharge Pressure Reset
Flow Supply Volume Reset Differential Pressure
Isolation Valve Position Heating Control Flow
Entering Water Temp Zone Temp Reset
Leaving Water Temp Minimum Volume Reset
Zone Temp
Supply Air Reset
Zone Pressurization Control

Utilities

Natural Gas Consumption

Electricity Consumption &
Demand
Water Consumption
Fuel Oil Quantity

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 BUILDING AUTOMATION SYSTEM
Maintenance Scheduling.

AKHWAN always focus to include programs for control that switch pumps and compressors from
operating equipment to stand-by on a scheduled basis. Also, programs that provide maintenance
schedules for equipment in every building system shall be included, complete with information on what
parts and toolsare needed to perform each task.

System Design Considerations.

Maintenance Scheduling. AKHWAN include programs for control that switch pumps and compressors
from operating equipment to stand-by on a scheduled basis. Also, programs that provide maintenance
schedules for equipment in every building system should be included, complete with information on what
parts and tools are needed to perform each task.

System Design Considerations. BAS’s require measurements at key points in the building system to
monitor part-load operation and adjust system set points to match system capacity to load demands.
Controlscannot correct inadequate source equipment, poorly selected components, or mismatched
systems. Energy efficiency requires a design that is optimized by realistic prediction of loads, careful
system selection, and full control provisions. System ability must include logs of data created by user
selectable features.
In new buildings and major renovations, the BAS shall have approximately 20 percent spare capacity for
future expansion. The system must provide for stand-alone operation of subordinate components. The
primary operator workstation must have a graphical user interface. Standalone control panels and terminal
unit controllers can have text-based user interface panels which are hand-held or fixed.

Energy Measurement Instrumentation. BAS shall have the capability to allow building staff to measure
energy consumption and monitor performance which is critical to the overall success of the system.
Electrical values, such as V, A, kW, KVAR, KVA, PF, kWh, KVARH, Frequency and Percent THD, should
be measured. See also Chapter 6: Electrical Engineering, Site Distribution, for separate metering of power
consumption.
Energy management measurements shall be totalized and trended in both instantaneous and time-based
numbers for chillers, boilers, air-handling units and pumps. Energy monitoring data shall be automatically
converted to standard database and spreadsheet format and transmitted to a designated PC.
Require measurements at key points in the building system to monitor part-load operation and adjust
system set points to match system capacity to load demands. Controls cannot correct inadequate source
equipment, poorly selected components, or mismatched systems. Energy efficiency requires a design that
is optimized by realistic prediction of loads, careful system selection, and full control provisions. System
ability must include logs of data created by user selectable features. In new buildings and major
renovations, the BAS shall have approximately 20 percent spare capacity for future expansion. The system
must provide for stand-alone operation of subordinate components. The primary operator workstation
shall have a graphical user interface. Standalone control panels and terminal unit controllers can have
text- based user interface panels which are hand-held or fixed.

Energy Measurement Instrumentation.

BAS shall have the capability to allow building staff to measure energy consumption and monitor
performance which is critical to the overall success of the system. Electrical values, such as V, A, kW,
KVAR,KVA, PF, kWh, KVARH, Frequency and Percent THD, should be measured Electrical Engineering,
Si Distribution, for separate metering of power consumption.

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Energy management measurements shall be totalized and trended in both instantaneous and time-based
numbers for chillers, boilers, air-handling units and pumps. Energy monitoring data shall be automatically
converted to standard database and spreadsheet format and transmitted to a designated PC.

STARTUP, TESTING AND BALANCING

EQUIPMENTS AND SYSTEMS
START-UP.
We always make sure that at the time of start-up of the A/E specify that factory representatives be present
for start-up of all major equipment, such as boilers, chillers and automatic control systems.

TESTING AND BALANCING.

We always take responsibility of the A/E to adequately specify testing, adjusting and balancing resulting in
not only proper operation of individual pieces of equipment, but also the proper operation of the overall
HVAC and plumbing systems, in accordance with the design intent.

PERFORMANCE TESTING.
A/E to specify performance testing of all equipment and systems including chillers, boilers, and other
systems for part load and full load during summer, winter, spring and fall season as per the schedules
specified by the designer.

PRESSURE AND LEAK TESTING.

We conduct Tests at static pressures equal to maximum design pressure of system and maximum leakage
allowable less than 50% of that allowed in HVAC Air Duct Leakage Manual.

A/E to specify IAQ testing for CO, CO2, volatile organic compounds, NO2, O3, and tobacco smoke. A/E
to specify operating tests on each air and hydronic system to measure and meet energy efficiency to specify
and validate peak summer and winter energy consumption and performance.

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