Components And Controls; Crankcase Heat (Cch); Controls (Hpc And Lpc) - Rheem RA13 Series Installation Instructions Manual

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
MAXIMUM SYSTEM CHARGE VALUES
RA13
Model Compressor
Size Model Number
18AJ ZP14KAE/ZP14K6E
24AJ ZP20KAE
30AJ ZP24K5E
36AJ ZP31K6E
42AJ ZP34K5E
48AJ ZP42K5E
60AJ ZP51K5E
36AC ZP31K6E-TF5
42AC ZP34K5E-TF5
48AC ZP42K5E-TF5
60AC ZP51K5E-TF5
36AD ZP31K6E-TFD
42AD ZP34K5E-TFD
48AD ZP42K5E-TFD
60AD ZP51K5E-TFD
48AY ZP42K5E-TFE
60AY ZP51K5E-TFE
High- and Low-Pressure Controls (HPC and LPC)
HPC and LPC are not installed on RA13**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�

COMPONENTS AND CONTROLS

• 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 energized for at
least 12 hours before the compressor is started�
(Disconnect switch is on and wall thermostat is off�)
MAXIMUM SYSTEM CHARGE VALUES
Charge Limit
Without Crankcase
Heat (1 Phase)
9.6 lbs.
MAXIMUM SYSTEM CHARGE VALUES
9.6 lbs.
9.6 lbs.
9.6 lbs.
12 lbs.
12 lbs.
12 lbs.
9.6 lbs.
12 lbs.
12 lbs.
12 lbs.
9.6 lbs.
12 lbs.
12 lbs.
12 lbs.
12 lbs.
12 lbs.
The low-pressure control (LPC) is an automatic-
reset which opens near 15 PSIG and closes near
40 PSIG�
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�
RA14
Model Compressor
Size Model Number
18AJ ZP14KAE/ZP14K6E
24AJ ZP20KAE
30AJ ZP24K5E
36AJ ZP29K5E
42AJ ZP34K5E
48AJ ZP39K5E
60AJ ZP49K6E
36AC ZP31K6E-TF5
42AC ZP34K5E-TF5
48AC ZP42K5E-TF5
60AC ZP51K5E-TF5
36AD ZP31K6E-TFD
42AD ZP34K5E-TFD
48AD ZP42K5E-TFD
60AD ZP51K5E-TFD
RA16
Model Compressor
Size Model Number
18AJ ZP14K6E
24AJ ZP21K6E
30AJ ZP24K6E
36AJ ZP31K6E
42AJ ZP34K6E
48AJ ZP38K6E
60AJ ZP49K6E
60BJ ZP49K6E
36AC ZP31K6E-TF5
42AC ZP34K6E-TF5
48AC ZP38K6E-TF5
60AC ZP49K6E-TF5
CAUTION:
The compressor has
Charge Limit
Without Crankcase
Heat (1 Phase)
9.6 lbs.
9.6 lbs.
9.6 lbs.
9.6 lbs.
12 lbs.
12 lbs.
12 lbs.
9.6 lbs.
12 lbs.
12 lbs.
12 lbs.
9.6 lbs.
12 lbs.
12 lbs.
12 lbs.
Charge Limit
Without Crankcase
Heat (1 Phase)
9.6 lbs.
9.6 lbs.
9.6 lbs.
9.6 lbs.
12 lbs.
12 lbs.
12 lbs.
12 lbs.
12 lbs.
12 lbs.
12 lbs.
12 lbs.
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