Scotsman SCE170 User Manual page 21

Service Diagnosis
SYMPTOM
Machine operates, no ice is
formed.
Compressor cycles on and off.
Frost on compressor
To check bin control system:
When curtain is closed, BOTH
curtain indicator lights on the
control board in the control box
should be ON, if not:
POSSIBLE CAUSE
Unit stuck in harvest cycle.
Refrigerant leak
Compressor will not operate
Hot gas valve stuck open.
Refrigerant leak.
Hot gas valve and purge valve
stay on after curtains close and
both curtain indicator lights are on.
Purge valve leaks thru.
Compressor overheats.
Some frost will not hurt.
TXV meters too much refrigerant. Replace TXV.
Curtain not closed properly
Sensor not in correct position
Curtain missing
Curtain sensor has failed.
October 1998
Page 21
SCE170
PROBABLE FIX
Check for curtain stuck closed.
Cubes too small, adjust bridge
thickness, see Cube Size/Bridge
thickness section
Locate leak, repair, replace dryer,
evacuate and weigh in nameplate
charge
Check compressor contactor coil.
Check compressor.
Check compressor start circuit
Replace hot gas valve.
Locate leak, repair, replace dryer,
evacuate and weigh in nameplate
charge.
Replace control board.
Clean or replace purge valve
Low on refrigerant. Repair leak,
evacuate and weigh in nameplate
charge
Air cooled - fan not blowing,
repair fan.
TXV not letting enough refrigerant
into evaporators, replace TXV.
Mechanical fault with compressor,
replace compressor.
Check start capacitor
Check start relay
Do nothing.
Check action of curtains
Place sensor assembly in correct
position
Replace curtain
Replace sensor assembly.