ICP HC4H3, Руководство по установке

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START − UP
Step 1
—
Preliminary Checks
1. Check that all internal wiring connections are tight
and that all barriers, covers, and panels are in place.
2. Field electrical power source must agree with unit
nameplate rating.
3. All service valves must be open.
4. Belly
− band crankcase heater must be tight on
compressor crankcase for those units with belly − band
heaters.
Step 2
—
Leak Test
Field piping and fan coil must be leak tested by pressure
method. Use R − 410A refrigerant at approximately 25 psig
backed up with an inert gas to a total pressure not to
exceed 245 psig.
NOTE : Leak detectors should be designed to detect HFC
(hydroflourocarbon) refrigerant.
Step 3
—
Evacuate and Dehydrate
Field piping and fan coil must be evacuated and
dehydrated.
Step 4
—
Charge System
Release charge into system by opening (backseating) liquid
and suction line service valves. F
Step 5
—
To Start Unit
Be sure that the field disconnect is closed. Set room
thermostat below ambient temperature. Operate unit for 15
minutes, then check system refrigerant charge. See
Refrigerant Charging section.
NOTE : When using in conjunction with underceiling fan
coils, refer to start − up instructions included with fan coil for
correct start − up procedures.
SERVICE
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in
personal injury or death.
Before installing, modifying, or servicing system,
main electrical disconnect switch must be in the
OFF position. There may be more than 1
disconnect switch. Lock out and tag switch with a
suitable warning label.
Outdoor Fan
A reinforced wire mount holds the outdoor fan assembly in
position. See Figure 10 for proper mounting position.
HC4H3 Unit Size, in. (mm)
18,24 30,36 48,60
0.433 (11.00) 0 0
A07401
Figure 10
-
Condenser Fan Mounting Positions
High − Pressure Relief Valve
The high − pressure relief valve is located in the compressor.
The relief valve opens at a pressure differential of
approximately 550 to 625
±
50 psig between suction (low
side) and discharge (high side) to allow pressure
equalization.
Internal Current and Temperature Sensitive Overload
The control resets automatically when internal compressor
motor temperature drops to a safe level (overloads may
require up to 45 minutes to reset). When an internal
overload is suspected of being open, check by using an
ohmmeter or continuity tester.
Pumpdown Procedure
The system may be pumped down in order to make repairs
on the low side without losing complete refrigerant charge.
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
Never open system to atmosphere while it is under a
vacuum.
When system must be opened for service, recover
refrigerant, break vacuum with dry nitrogen before opening
system.
1. Attach pressure gage to suction service valve gage
port.
2. Frontseat the liquid/mixed phase line valve.
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
The unit coils hold only the factorydesignated amount
of refrigerant. Additional refrigerant may cause units
to relieve pressure through the compressor internal
pressure relief valve (indicated by a sudden rise of
suction pressure) before suction pressure reaches 20
psig. If this occurs, shut off unit immediately then
frontseat the suction valve and remove and recover
excess refrigerant following accepted practices
3. Start unit and run until suction pressure reaches 20
psig.
4. Shut unit off and frontseat suction valve.
5. De − pressurize low side of unit and recover refrigerant
following accepted practices.
High − Pressure Switch
The high − pressure switch, located on discharge line,
protects against high discharge pressures caused by such
events as overcharge, condenser − fan motor failure, system
restriction, etc. It opens on pressure rise at about 650 ± 10
psig. If system pressures go above this setting during
abnormal conditions, the switch opens.
!
WARNING
PERSONAL INJURY HAZARD
Failure to follow this warning could result in
personal injury or death.
DO NOT attempt to simulate these system
abnormalities − high pressures pose a serious
safety hazard.
The high − pressure switch is checked with an ohmmeter. If
system pressure is below 625 psig switch shows continuity.