Westinghouse WPAPH-090CA4, Service Manual

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WESTINGHOUSE PACKAGE A/C MANUAL R-410A : 220V: 60Hz
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5. List of Function
5.1 Standard specification
A. General
The Packaged cooling or combination heating and cooling unit is suitable for mounting on the roof or
ground. The packaged unit consists of scroll compressors, evaporator coil, condenser coil, control wiring
and interconnecting piping- all factories assembled and mounted on heavy gauge G-90 galvanized steel
sheet press formed base, ready for field connection to utilities and ducts. The packaged unit is of rigid
construction with holes provided in the base rails for overhead rigging. The unit is provided with an integral
weather resistant control panel.
These units are rated and tested in accordance with ARI standard 210/ARI 360.
B. Unit enclosure
Panels are of heavy gauge, G-90 galvanized steel sheet with removable access panels, completely
weatherized for outdoor installation and properly reinforced and brazed. Panels and access door are
provided for inspection and access for all internal parts. Enclosures are provided with adequately
reinforced points of support for setting in the unit. Steel sheet panels are zinc-coated and galvanized by the
hot dip process of lock forming quality conforming to ASTM A 653 commercial weight G-90, followed by
baked on electrostatic polyester dry powder coat paint, on all external panel.
C. Compressor
Compressors are scroll for all the models. They are provided with all the standard controls and accessories
necessary for safe operation. These are equipped with internal motor protector; factory installed crank case
heater and rubber vibration isolator for quiet and efficient operation.
D. Air-cooled condensing section
1. The air-cooled condensing section is enclosed within the unit housing and consists of condenser coil,
fan(s) electric motor(s) and inherently protected compressor(s). As an option, enhanced coated aluminum
fins may be provided. Tube support sheets are galvanized steel, formed to provide structural strength.
2. Fans are propeller type, direct driven, upward discharge and provided with fan grille mounted on the
casing.
3. Motors are totally enclosed air-over type with class F insulation. Inherent thermal protection is automatic
reset type.
E. Evaporator coil section
1. All cooling coils are of enhanced louvered fins and inner grooved copper tubes with wall thickness of
0.3mm, mechanically bonded to
aluminum fins. Return bend has 0.022 inch thickness (0.56mm). As option,
enhanced coated aluminum fins may be provided. Tube support sheets are galvanized steel, formed to
provide structural strength.
2. Drainage pan: An insulated drainage pan made of G-90 galvanized steel is provided, for additional
corrosion protection.
3. Insulation: Insulation is supplied in adequate density and thickness for all units to prevent condensation
from forming on the unit casing. Insulation meets the requirements of NFPA 90A and is protected against
deterioration and erosion from air currents.
F. Evaporator fan
Evaporator fan is of centrifugal forward-curved blade design capable of handling total required CFM and
static pressure in the low and the medium ranges. Casings are made of galvanized steel. Blower motors
are of open drip proof type (totally enclosed types are optional) and conform to NEMA MG-1 and MG-2.
Blower motor is mounted on adjustable base and secured by locking device. Fan wheels shafts and
bearing are selected to operate at 25% below first critical speed. Pillow block bearing are selected for at
200,000 hours average life at design operating conditions. Shaft is turned, ground and polished from solid