Scotsman CME650R - Manual (Page 24)

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
CME650R
March 1994
Page 24