Service Diagnosis - Scotsman MDT5N40A-1B Manual

SERVICE DIAGNOSIS

Symptom
No ice made, nothing operates
Unit operates, no ice is vended
Compressor on, auger motor is off Auger motor windings open
Compressor does not operate
Possible Cause
Unit off due to no power
Unit off due to master switch in
OFF position
Unit off due to low water level
Unit off due to ice level sensors
(photo-electric eyes) blocked
Unit off due to scale on water level
sensor
Unit off due to water temperature
too high
Check for ice in the bin
Check for jam up of ice in
dispense chute
If there is ice, check that the bin
vane rotates. if not
If there is power to the bin drive
motor, but the vane does not turn
Auger motor relay does not make Replace circuit board
Contactor stuck
Off due to high pressure control
open
Contactor coil is open
Contactor contacts do not make
Start capacitor failed
Potential relay failed
Compressor windings open
Compressor locked
May 2001
Page 21
MDT5N25 & MDT5N40
Probable Correction
Restore power
Switch master switch to ON
Check water supply, filter, strainer,
float valve. Correct water supply
Check/clean ice level sensors
Clean water level sensor
Thermistor will shut down unit at
temperatures over 110
If no ice, check that ice maker can
make ice
Check that machine cannot keep
up with needs
Pull chute down and allow ice to
fall out. Return chute to its normal
place.
Check for power to the bin drive
motor, if none, check condition of
Touch-Free ice sensor.
Disconnect electrical power,
remove all ice, check mechanical
condition of ice vane. Replace if
broken.
If ice vane is mechanically sound,
check bin drive, replace if broken.
Replace auger motor
Replace contactor
Check condenser, fan motor, fan
blade, or water supply on water
cooled.
Replace contactor
Replace contactor
Replace start capacitor
Replace relay
Replace compressor
Replace compressor
o
F.