Evaporator Assembly; Compressor Electrical Diagnostics - Welbilt Multiplex FreshBlender Service Manual

Component Check Procedures

EVAPORATOR ASSEMBLY

Function
Freezes water to the evaporator wall and the ice is removed
with an auger. The auger transfers the shaved ice upward
where it is compressed through an extruder and exits the
top of the evaporator.
Check procedure
The most common failure is a buildup of lime scale or
minerals on the evaporator wall and auger. This buildup
applies additional pressure on the evaporator assembly
and results in rotation sensor trips, gearmotor trips or
mechanical failure of the evaporator.
1. Water leakage is normally a failed seal due to a
buildup of scale and mineral or a bearing failure.
Disassembly,inspection and cleaning are required
when water leakage is present.
2. Cleaning - For all other issues cleaning is the first step:
A. Premix 11 ounces of cleaner with 6 ounces of water
in a non metallic container.
B. Add the entire solution to the evaporator and allow
to soak for a minimum of 4 hours.
C. Test run and check operation. If the issue is not
resolved, proceed with the next step.
3. Disassemble, inspect and clean components with a
cloth soaked in ice machine cleaner. Removing the ice
chute will expose the ice breaker and extruder cover.
Removing the extruder cover allen bolts will allow the
auger assembly to be lifted and removed from the
evaporator barrel for inspection and cleaning. Refer to
exploded view for disassembly and identification. Clean
and replace parts as required.
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COMPRESSOR ELECTRICAL DIAGNOSTICS

The compressor does not start or will trip repeatedly on
overload.
Check Resistance (Ohm) Values
NOTE: Compressor windings can have very low ohm values.
Use a properly calibrated meter.
Perform the resistance test after the compressor cools. The
compressor dome should be cool enough to touch (below
120°F/49°C) to assure that the overload is closed and the
resistance readings will be accurate.
SINGLE PHASE COMPRESSORS
1. Disconnect power then remove the wires from the
compressor terminals.
2. The resistance values between C and S and between
C and R, when added together, should equal the
resistance value between S and R.
3. If the overload is open, there will be a resistance
reading between S and R, and open readings between
C and S and between C and R. Allow the compressor to
cool, then check the readings again.
CHECK MOTOR WINDINGS TO GROUND
Check continuity between all three terminals and the
compressor shell or copper refrigeration line. Scrape metal
surface to get good contact. If continuity is present, the
compressor windings are grounded and the compressor
should be replaced.
COMPRESSOR DRAWING LOCKED ROTOR
To determine if the compressor is seized, check the amp
draw while the compressor is trying to start.
The two likely causes of this are a defective starting
component or a mechanically seized compressor.
To determine which you have:
1. Install high and low side gauges.
2. Try to start the compressor.
3. Watch the pressures closely.
A. If the pressures do not move, the compressor is
seized. Replace the compressor.
B. If the pressures move, the compressor is turning
slowly and is not seized. Check the capacitors and
relay.
COMPRESSOR DRAWING HIGH AMPS
The continuous amperage draw on start-up should not be
near the maximum fuse size indicated on the serial tag.
Section 7
Part Number REV00 04/08/2020