SERVICE DIAGNOSIS: Electrical and/or Adjustments
SYMPTOM
POSSIBLE CAUSE
PROBABLE FIX
Machine does not operate
No power
Reconnect power
High pressure control open
Reset, check machine
High temperature cut out open
Hot gas valve leaks thru, replace
P. C. Board Open
Replace board
Master switch open
Test/replace
Timer contacts open
Replace timer
Bin thermostat holding machine
off
Test thermostat, replace if
contacts stuck open.
Makes thick ice/freezes up
Harvest Cycle too short
Adjust timer
Low water pressure
Check water filter or supply
Check inlet water valve screen
and flow control.
Hot gas valve defective
Replace hot gas valve
Cubes too small
Adjust cube size
Cube size control stuck open
Replace cube size control
Runs, makes no ice
Pump problem or water leak in
reservoir
Check water system and pump
Water inlet valve either lets in no
water or leaks through
Replace inlet water valve
Timer stuck
Replace timer
Relay does not energize; unit
stuck in harvest
Replace relay
Long freeze cycle
Water inlet valve leaks through
Replace inlet water valve
Water temperature too high
Advise user
Cubes too small
Cube size set wrong
Adjust cube size
Cubes size control stuck closed
Replace cube size control
Cubes too large
Water inlet valve leaks through
Replace inlet water valve and
adjust cube size control
Compressor cycles on and off on
pump down control
Low refrigerant charge
Locate leak, repair, replace drier,
evacuate and weigh in nameplate
charge.
Liquid line valve or drier restricted Check and replace
TXV restricted
Check and replace
Head pressure control valve not
working (low condensing temp.)
Check/replace head pressure
control valve
Compressor will not run
Low pressure control will not close Check pump down control for
proper operation
Contactor coil open
Check/replace contactor
Compressor windings open
Check replace compressor
Unit cycles on and off anytime in
any cycle
Loose connection in PC board
Replace PC board
CME500R
March 1994
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