8-2
Mechanical Diagnosis
CSR-20 & CSR-40, September 1999
Condition
Possible Cause
Remedy
Compressor does not
Defective compressor
Replace compressor
operate — no amperage
draw (continued)
Controller shut unit down on
Let compressor cool and controller will
Compressor Over Temperature
reset automatically. Check liquid injection
(alarm 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.
Compressor does not
Rotating scroll stuck
Replace compressor
operate; excessive
amperage draw or
Seized or frozen compressor bearings
Replace compressor
intermittent cycling
on overload
Improperly wired
Check/correct wiring against wiring diagram
Low line voltage
Check line voltage — determine location of
voltage drop
Contacts in compressor contactor not
Check by operating manually. Repair or
closing completely
replace
Open circuit in compressor motor
Check motor stator connections. Check
winding
stator winding for continuity. If open,
replace compressor
Defective compressor motor internal
Replace thermal overload protector or
thermal overload protector
compressor
Refrigerant overcharge or high
Check for restricted filter drier or high side,
side restriction causing cycling
and refrigerant overcharge
on high pressure cutout
Inefficient condenser operation
Check condenser airflow, condenser
causing cycling on high pressure
fan motor, fan blade, condenser grille,
cutout
condenser coil temperature sensor, water
pressure switch (option), water flow rate
(option) and water-cooled condenser-
receiver tank (option)
