6–1
T-340
SECTION 6
TROUBLESHOOTING
Condition
Possible Cause
Remedy / Reference
6.1 Unit Will Not Start Or Starts Then Stops
No power to unit
External power source OFF
Turn on
Start-Stop switch OFF or defective
Check
Circuit breaker tripped or OFF
Check
Autotransformer not connected
Loss of control power
Circuit breaker OFF or defective
Check
Control transformer defective
Replace
Fuse (F3A/F3B) blown
Check
Start-Stop switch OFF or defective
Check
Component(s) not operating
Evaporator fan motor internal protector open
Condenser fan motor internal protector open
Compressor internal protector open
High pressure switch open
Heat termination thermostat open
Replace
Malfunction of current sensor
Replace
Compressor hums, but does
not start
Low line voltage
Check
Single phasing
Check
Shorted or grounded motor windings
Compressor seized
6.2 Unit Operates Long Or Continuously In Cooling
Container
Hot load
Normal
Defective box insulation or air leak
Repair
Refrigeration system
Shortage of refrigerant
Evaporator coil covered with ice
Evaporator coil plugged with debris
Evaporator fan(s) rotating backwards
Air bypass around evaporator coil
Check
Controller set too low
Reset
Compressor service valves or liquid line shutoff valve
partially closed
Open valves completely
Dirty condenser
Compressor worn
Current limit (function code Cd32) set to wrong value
Economizer solenoid valve malfunction
Digital unloader valve stuck open
Replace
Electronic expansion valve
Replace