6–5
T-340
High suction pressure with
low superheat
Foreign material in valve
Failed suction pressure transducer (SPT) or evapora
-
tor pressure transducer (EPT)
Replace
Electronic expansion valve (EEV) control malfunction Replace
Improperly seated powerhead
Ensure powerhead is
locked and in place
Liquid slugging in compressor
Failed suction pressure transducer (SPT) or evapora
-
tor pressure transducer (EPT)
Replace
Failed electronic expansion valve (EEV)
Replace
6.13 Autotransformer Malfunction
Unit will not start
Circuit breaker (CB-1 or CB-2) tripped
Check
Autotransformer defective
Power source not turned ON
Check
460 VAC power plug is not inserted into the receptacle
6.14 Water-Cooled Condenser Or Water Pressure Switch
High discharge pressure
Dirty coil
Non-condensibles
Condenser fan
starts and stops
Water pressure switch malfunction
Check
Water supply interruption
Check
6.15 Compressor Operating in Reverse
NOTE
The compressor may start in reverse for up to 10 seconds to determine correct phase rotation if
required for phase detection.
CAUTION
!
Allowing the scroll compressor to operate in reverse for more than two minutes will result in
internal compressor damage. Turn the start- stop switch OFF immediately.
Electrical
Incorrect wiring of compressor
Check
Incorrect wiring of compressor contactor(s)
Incorrect wiring of current sensor
Condition
Possible Cause
Remedy / Reference
