Trouble Shooting Table - Scotsman NU150 Service Manual

NU Undercounter Ice Machine Service Manual

Trouble shooting table

Symptom Possible Cause
Abnormal power supply
The fuse on PC board blew
Unit does not
The
run
abnormally(such
temperature protection)
Ice full
Abnormal water supply
Low voltage
Non-condensable
Compressor
system
runs
intermittently
Compressor starting device
with loose wires
Mechanical problem
Ice making cycle too short
Expansion
blocked
Cubes too
small Moisture in the system
Shortage of water
Shortage of refrigerant
Shortage of water
Dirty water supply
Cloudy ice
Accumulated impurities
Water
failure
Shortage of
Water spilling out through ice
water
chute
Water inlet solenoid valve not
opening
Water leak in water tank
Water inlet valve blocked
Water drain valve leak
machine is stopped
as high
gas
valve partially
temperature sensor
Suggested Correction
Check power supply voltage, if no voltage, check
power supply line
Check power supply voltage, if it is low, contact
power supply company
Replace the fuse. If the fuse is broken again, check
the cause.
Press the MODE key on the PC board to reset, the
machine starts or starts automatically 2 hours later
or unplug the power plug, plug it again 3 minutes
later, the machine starts.
Adjust the position of the ice cubes in the storage
bin to let the ice trough reset and then start the
machine
See the processing method for water-shortage
Check circuit for overloading
in Check power supply voltage, if it is low, contact
power supply company
Purge the system and re-charge
Check for loose wires in starting device
Replace compressor
Check the distance between the ice thickness and
the evaporator plate
Check the expansion valve, if damage , replace
it
Purge the system and re-charge
See the processing method for water-shortage
Check for leaks in the refrigerating system &
recharge
See the processing method for water- shortage
Use water softener or water filter
Cleaning as the procedure
Replace the water temperature sensor
Tighten the screws on the clamping plate of the
PVC pipe to reduce water flow
Check, if damage, replace it
Check for the leaking points and repair it.
If necessary, replace it.
Replace the water inlet valve
Check, if damage, replace it
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Trouble Shooting Tabl