Rheem 018J*Z, Руководство по установке

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18
HIGH AND LOW PRESSURE CONTROLS
(HPC OR LPC)
These controls keep the compressor from operating in pressure ranges which can
cause damage to the compressor. Both controls are in the low voltage control cir-cuit.
High pressure control (HPC) is a manual reset which opens near 610 PSIG. Do not
reset arbitrarily without first determining what caused it to trip.
The low pressure control (LPC) is an automatic reset which opens near 50 PSIG and
closes near 95 PSIG.
NOTE: High and low pressure controls are standard on all (-)ANL, (-)APL, (-)APM
models.
FIELD INSTALLED ACCESSORIES
COMPRESSOR CRANKCASE HEAT (CCH)
While scroll compressors usually do not require crankcase heaters, there are
instances when a heater should be added. Refrigerant migration during the off cycle
can result in a noisy start up. Add a crankcase heater to minimize refrigeration
migration, and to help eliminate any start up noise or bearing “wash out.”
NOTE: A crankcase heater heater should be installed if: the charge of the system
exceeds the values in Tables 4 and 5, if the system is subject to voltage variations
or when a low ambient control is used for system operation below 55°F.
All heaters are located on the lower half of the compressor shell. Its purpose is to
drive refrigerant from the compressor shell during long off cycles, thus preventing
damage to the compressor during start-up.
At initial start-up or after extended shutdown periods, make sure the heater is ener-
gized for at least 12 hours before the compressor is started. (Disconnect switch on
and wall thermostat off.)
TABLE 9
MAXIMUM SYSTEM CHARGE VALUES (-)ANL
(-)ANL Charge Limit Charge Limit
Model Compressor Without Crankcase Without Crankcase
Size Model Number Heat (3 Phase) Heat (1 Phase)
18 ZP16K5E 8 lbs. 9.6 lbs.
24 ZP21K5E 8 lbs. 9.6 lbs.
30/31 ZP25K5E 8 lbs. 9.6 lbs.
36/37 ZP34K5E 10 lbs. 12 lbs.
42 ZP36K5E 10 lbs. 12 lbs.
43 ZP38K5F 10 lbs. 12 lbs.
48/49 ZP42K5E 10 lbs. 12 lbs.
60 ZP54K5E 10 lbs. 12 lbs.
TABLE 10
MAXIMUM SYSTEM CHARGE VALUES (-)APL
(-)APL Charge Limit
Model Compressor Without Crankcase
Size Model Number Heat (1 Phase)
18 ZP16K5E 9.6 lbs.
24 ZP20K5E 9.6 lbs.
30 ZP24K5E 9.6 lbs.
36 ZP31K5E 9.6 lbs.
42 ZP36K5E 12 lbs.
48 ZP42K5E 12 lbs.
60 ZP51K5E 12 lbs.
TABLE 11
MAXIMUM SYSTEM CHARGE VALUES (-)APM
(-)APM Charge Limit
Model Compressor Without Crankcase
Size Model Number Heat (1 Phase)
18 ZP16K5E 9.6 lbs.
24 ZP20K5E 9.6 lbs.
30 ZP24K5E 9.6 lbs.
36 ZP31K5E 9.6 lbs.
42 ZP34K5E 12 lbs.
48 ZP42K5E 12 lbs.
60 ZP51K5E 12 lbs.