Scotsman NME1854R - Manual (Page 25)

NME1854R & FME2404R
January 2000
Page 25
SERVICE DIAGNOSIS: Condition
Symptom Possible Cause Probable Correction
No ice is made, nothing operates Unit off due to no power. Restore power
Unit off due to master switch in Off
position
Move master switch to ON
Unit off due to low water level in
reservoir
Check water supply, filter and float
valve.
Unit off due to ice level sensors
(photo-electric eyes) blocked
Check/clean ice level sensors
Unit off due to scale on water level
sensor
Clean water level sensor
Unit off due to high pressure control
open
Check for remote condenser fan
motor failure or power interruption to
the fan motor
Auger motor hums but does not turn Auger can’t turn. Circuit board has not
yet shut unit down.
Unit is shut down Circuit board has shut ice machine
down due to high auger motor amp
draw. Check for cause of high amp
draw, including bearings, gear motor
condition and scale on auger &
evaporator.
Pump down pressure control open,
very low suction pressure
Auger not turning due to: motor
failure; auger relay failure on circuit
board; or gears stripped. Check drive
train.
Liquid line valve not opening due to
coil failure or failure of compressor
relay on circuit board
TXV restricted or not metering. Check
bulb temperature.
Lack of refrigerant. Check for a leak.
No power to circuit board Check harness
Hi or Low pressure switches open
Circuit board gear motor relay open Check / replace board
Water level or ice level sensor failed Check / replace sensor
No ice, auger motor is turning Compressor contactor coil is open Check / replace contactor
Compressor will not start Check start capacitor
Check start relay
Check compressor windings
Circuit board relay will not close Check / replace board
Pump down pressure switch does not
close, liquid line valve open and
suction pressure high
Check pump down switch contacts