Components And Controls; Crankcase Heat (Cch); Controls (Hpc And Lpc) - Rheem RA1460AJ1NA Installation Instructions Manual

COMPONENTS AND CONTROLS

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 refrigerant
migration and to help eliminate any start up noise
or bearing "wash out."
NOTE: A crankcase heater should be installed if:
• The system charge exceeds the values listed in
the adjacent tables,
• The system is subject to low voltage variations,
or
• When a low ambient control is used for system
operation below 55°F�
High- and Low-Pressure Controls (HPC and LPC)
HPC and LPC are not installed on RA14**AJINA,
but can be field installed using the followiing
kit numbers: RXAB-A0z (high pressure control)
and RXAC-A0Z (low pressure control)� 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 circuit�
The high-pressure control (HPC) is an automatic-
reset which opens near 610 PSIG and closes near
420 PSIG�
28
RA14
Model Compressor
Size Model Number
18 ZP14KAE
24 ZP20KAE
30 ZP24K5E
36 ZP29K5E
42 ZP34K5E
48 ZP39K5E
60 ZP49K6E
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 energized for at
least 12 hours before the compressor is started�
(Disconnect switch is on and wall thermostat is off�)
Charge Limit
Without Crankcase
Heat (1 Phase)
9.6
9.6 lbs.
9.6
9.6 lbs.
9.6
9.6 lbs.
9.6
9.6 lbs.
12
12 lbs.
12
12 lbs.
12
12 lbs.
The low-pressure control (LPC) is an automatic-
reset which opens near 15 PSIG and closes near
40 PSIG�
CAUTION:
an internal overload protector� Under some
conditions, it can take up to 2 hours for this
overload to reset� Make sure overload has had
time to reset before condemning the compressor�
The compressor has