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CRR-20 & CRR-40, September 1999
Condition
Possible Cause
Remedy
Compressor does not
Controller ON; unit start
Wait up to 3 minutes for compressor
operate — no amperage
sequence still timing
start-up
draw.
No power to unit (condenser and
Locate fault and repair: power source,
evaporator fans do not operate)
power plug, CB1 main circuit breaker, motor
contactor, motor terminals, motor
Open in 24 Vac
Check fuses and On/Off switch. Replace or
control circuit
repair as required
Container temperature does not
Adjust controller setpoint
demand compressor operation
Compressor contactor inoperative
Replace compressor contactor
No output signal from controller
Diagnose and replace output module or
output module
controller
Unit on defrost
Turn unit On/Off switch OFF and then ON
again
Defective high pressure cutout switch
Replace high pressure cutout switch
High condenser head pressure
Check refrigeration system and correct
causing high pressure cutout
fault
Defective compressor
Replace compressor
Controller shut unit down on
Let compressor cool and controller will
Compressor Over Temperature
reset automatically. Check liquid injection
(fault code 82)
valve and compressor temperature sensor
Compressor motor internal thermal
If compressor contactor is energized, wait
overload protection open
60 minutes for protector to cool and reset.
Mechanical Diagnosis
8
Diagnosis
Summary of Contents for CRR-20
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