Scotsman Prodigy Plus D Series Service Manual - Manual (Page 44)

N0422, F0522, N0622, F0822, N0922, F1222, N1322, F1522
Air, Water or Remote Service Manual
December 2014
Page 44
Symptom Probable Cause Possible Correction
Compressor is not operating Contactor not pulled in Check voltage to coil of contactor,
if correct, check coil of contactor
Check if Low or High pressure cut
outs open, Code 4 in code display
Check if remote pump down switch
not closed - if open, check low side
pressure and liquid line valve
Check for control board relay not
supplying power to contactor
Compressor overheated Check for low refrigerant charge
Check for high TXV superheat
Check for high amp draw, possible
start relay keeping start winding
powered
Compressor overload open Check for overheating, or over
amp draw
Compressor will not start Check start relay and start
capacitor
Check voltage at compressor
Check voltage at contactor
Check compressor windings
Compressor on, no refrigeration Low charge Check system charge
Condenser dirty Check condenser
Remote - liquid line valve restricted Check liquid line valve
TXV not metering
Check superheat
Auger not turning Check gear reducer
Remote headmaster in bypass
mode
Check headmaster
Inefficient compressor Check compressor amp draw, if
normal not likely inefficient
Compressor internal relief open Check suction and discharge
pressure. Relief valve opens at a
pressure differential between 450
and 550 and will not re-close until
differential between suction and
discharge is reduced to less than
450.
Service Diagnosis - Refrigeration System Failure