Service manual

Service Diagnosis:
SYMPTOM POSSIBLE CAUSE PROBABLE FIX
Ice is made, but will not harvest Will not harvest due to hot gas
valve not opening.
Check for voltage to coil in
harvest, if there is voltage
replace hot gas valve
Slow/incomplete harvest due to
hot gas valve not fully open.
Check low side pressure in
harvest, replace hot gas valve if
too low with correct ref. charge.
Makes ice, but very little High discharge pressure, due to
dirty condenser; faulty fan motor;
not enough water thru water
cooled condenser, high water
temperatures, water reg. valve set
too high.
Check for causes of high
discharge pressure and correct.
Inlet water temperatures and
room ambient very high
Advise user, suggest additional
room cooling.
Long freeze cycle due to hot gas
valve leaking thru.
Check temperature of tubes to
and from hot gas valve; there
should be a temperature drop
across the valve in the freeze
cycle. Replace valve if temps are
nearly equal.
Compressor inefficient Check/replace compressor
Cubes are wrong size/shape Ice size thermostat not adjusted
properly
Adjust ice size thermostat; use
gauge shipped with machine
Freeze cycle too short due to
heater open
Check/replace heater on ice size
thermostat probe tube.
Water system is restricted with
minerals
Clean water system with
Scotsman Ice Machine Cleaner
Ice thickness probe tube covered
with minerals
Clean tube with ice machine
cleaner
Not enough water Check water supply pressure
Check water supply for restrictions
Too much superheat Check superheat, replace TXV if
too high.
Check hot gas valve for leak-thru;
replace if leaks thru.
Ice fused together in bin Ice in bin too long Advise user to pour water on ice
to ease removal
Too many minerals in water Suggest water treatment to user.
SLC400
November 1994
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