Air Conditioning Unit (Explosion proof) For
Instrument Local Control Panel
TECH. SPECIFICATION FOR EXPLOSION PROOF WINDOW AC UNIT
1-DESIGN CONDITION:
TOTAL COOLING CAPACITY: 1 TON REFRIGERANT (12,000
BTU/HR)
AMBIENT TEMPERATURE: 125 deg. F = 52 deg. C
HAZARDOUS AREA CLASSIFICATION: CLASS 1 DIVISION 2, GAS GROUP
B,C, & D of T3
EXTERNAL STATIC PRESSURE: FREE FLOW
REFRIGERANT GAS: R-134a
Evaporator fan Air flow: 400 CFM (minimum)
2-QUALITY ASSURANCE:
2.1-MANUFACTURERS:
The unit must be of an internationally reputed and from VEC approved make
and must have reference record of performance in Kuwait environment (not
less than 5 years)
2.2 OEM MANUFACTURED:
The unit must be OEM manufactured to be suitable in hazardous locations
(cannot be third-party or not be retro-fitted)
2.3-QUALITY:
Units shall be the highest in quality and all manufacture procedures shall be
according to the ISO 9001 quality management system and ISO 14001
environmental management system. Relevant certificates shall be furnished
during bidding.
2.4-STANDARD:
Unless specified otherwise, the HVAC equipment shall conform in design,
materials and performance in accordance with shell DEPs version 33 as listed
below. the supplier shall also refer to the relevant ASHRAE standards; where
the appropriate ASHRAE standard exists, the supplier shall request an approval
form the company to use an appropriate standard or other international
standard.
- SHELL DEP-31.76.10.10-Gen.
- AHRI - AHRI Certified for Original Equipment Manufacturer (OEM)
2.5-RATED, TESTED, LISTED, CERTIFIED & LABELED:
Units shall be tested, listed, certified and labelled to its rated and manufacture
standard by nationally recognized testing laboratory approved by OSHA, UL,
etc.
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3-UNIT SPESCIFICATION:
3.1- UNIT CASING:
Unit casing shall be weatherproof construction, suitable for outdoor installation,
made of heavy gauge (18Gauge). Insulation gaskets to be provided between
dissimilar joints/connections.
3.2 COMPRESSOR:
The compressor shall be hermetic scroll or reciprocating type. Compressor
Nominal Capacity shall be 18,000 BTU/HR minimum.
3.3 CONDENSER:
The air-cooled condenser shall be the multi-pass cross-finned tube type
equipped with copper plated fins mechanically bonded to seamless copper
tubes (Double brazing). Coil shall be coated with anti-corrosion coatings on
refrigerant coils and all copper tubing (including insulated tubes) for maximum
of 10,000 hours ASTM B117 Salt spray test. It shall be suitable for sever
sulphuric area.
3.4 DIRECT EXPANSION COOLING COIL (EVAPORATOR).
Coil shall be multi-pass finned tube, equipped with copper plates fins
mechanically bounded to seamless copper tubes with double brazing. Coil shall
be dry type complete with strainer, expansion valve and distributor.
Coil shall be coated with anti-corrosion coatings on refrigerant coils and all
copper tubing (including insulated tubes) for maximum of 10,000 hours ASTM
B117 Salt spray test. It shall be suitable for sever sulphuric area
3.5 CONDENSER FAN AND FAN MOTOR.
The condenser fan(s) shall be aluminum propeller axial type, statically and
dynamically balanced, direct drive, up flow discharge with safety guard.
Fan motor(s): shall have permanently lubricated bearing, built-in thermal over
load protection and shall company with electrical specification there off. Motor
shall be class (f) insulation, drop-poof enclosure and Suitable for Hazardous
area class 1, Division 2, Gas Group B, C & D.
3.6 EVAPORATOR FAN, MOTOR AND STARTER.
Fan shall be centrifugal backward curved multi-blade type with adjustable v-
belt drive or direct driven, statically and dynamically balanced. Impeller and
fan casing shall be constructed of heavy gauge (16gauge) stainless steel 316L,
well protected against corrosion and finished factory coating. Fan to be
selected for their maximum efficiency to operate quietly when handling the
required air volume without over loading the fan motor (Motor Fan curve to be
submitted during GAD approval). Shaft bearing shall be of permanent
lubricated self-aligning type.
Fan (s) motor: shall be totally enclosed drip-proof, induction type, squirrel-
cage, air-over and class “f” insulation with internal thermal current protection.
and Suitable for Hazardous area class 1, Division 2, Gas Group B, C & D.
3.7 ELECTRIC FEATURES:
- Unit shall be rated for available power supply system of 240/1ph/4wire/50hz
(+/-5% volt & +/- 2.5% Hz)
- All motor shall be rated for 240/3ph/4wire/50hz and control volt shall be 24v
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- Control & power panel shall be furnished with suitable gland for incoming
power supply and shall include the following:
a. MCCB with provision to control (ON/OF) from outside the panel
b. Thermal overload protection and Single-phase preventer
c. selector switch with indication lamp for compressor & motors (blower &
condenser) showing its status (off/running/trip)
d. Return Air & Set Point temperature Indicator (shall be visually visible from
outside panel)
e. Earth Leakage relay
d. Panel door shall be rigidly hinged open/close type
f. Indidual fuse with casing for motors & compressor
g. Alarm/Control/HP Alarm Reset switch press type
- All required Electrical arcing components to be installed in NEMA 7 explosion
proof enclosure. Suitable for Hazardous area class 1, Division 2, Gas Group B, C
&D
- SS Name plate with engraved details of equipment with all motor/compressor
rating shall be available near to electrical panel
3.8 CONTROL AND OTHER DEVICES:
- Internal thermal motor protector for condenser, evaporator fan motor &
compressor.
- Safety electrical interlocking of evaporator fan motor with compressor
- Auto-Rest for LP switch and Manual reset HP switch (HP Switch shall be
Readily Accessible from outside).
- Time guard circuit for preventing compressor rapid recycling
- Time delay relay for sequence starting of compressor
- External overload relay for each motor, adjustable type
- Thermostatic expansion valve
- Indidual pressure gauges (glycerin filled) for refrigeration circuit visually
visible from outside and provision for gas charging ports (LP & HP) from outside
the equipment
- Return air filter plenum: With 1”, return air filter (metallic, cleanable
type)
- Supply & Return Air section with 4” Extension (SS316L + Insulation) and
Flanged Joint with bolts (insulated) and gaskets.
- All bolts, washers and accessories shall be of SS316L
- Vibration Absorber in Compressor side
- Drain line shall be of SS316 and routed outside Unit
- Vibration Absorber in Compressor side pipes
- Condenser fan motor shall be equipped with grill / guard, Guard and
motor shall be accessible from outside.
- Maximum allowable Minimum Circuit Ampacity (MCA) – 16 Amps
- Maximum Overcurrent Protection (MOP) – 20 Amps
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4- GUARANTEE:
One year for the whole A/C unit and five years for compressor from the date of
approval & end user receiving in Company's Warehouse.
Equipment and compressor guarantee certificate shall be delivered with
Equipment supply.
5- ORIENTATION
Drawing attached.
As this job is for replacing the existing equipment, supplier shall follow the
procedure:
1. Orientation drawing shall be submitted to Company for prior approval
2. Company shall mark on the drawing supply air opening, return air
opening, power/control cable access opening, drainage opening, holding screw
opening and filter provision.
3. All marked opening shall be incorporated to the manufacturing. In case of
any equipment not matching with the existing place, supplier will take a
response to correct deviation.
6- Mounting: Flange mounting on Panel Supply/Return Opening Flanges
7- TESTING:
a) Factory acceptance test; Equipment performance test shall be carried out
and offered for witness by (KNPC) Company Engineers as per standard AHRI.
(From the ordered Qty., 100% of Equipment shall be tested at factory).
b) Condenser and Evaporator pressure test certificate shall be provided
for Company approval at Factory inspection stage.
c) Third party certificate from Certified body/agency/lab required
for Conformity to the Hazardous area classification (Expl. proof)
8- Spares /Loose Supply:
- 02 set of spares Each Spare of Control Breaker, Overload, ELR, MCCB,
Temperature controller, Relays, Timer & Expansion Valve on each
purchase order.
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