Sub-Zero Wolf 506UI, Service Manual

Page: 38 / 52

Page 38
Model 506 (UC Ice Maker)
Model 506 (UC Ice Maker)
Component Access & Removal
4-13
#3752200 - Revision B - May, 2006
Compressor and Starting Components
Starting Relay
The starting relay is a magnetic current type that plugs
directly onto the compressor terminals. The unit com-
partment will need to be pulled out to access the com-
pressor and the starting components.
(See Figure 4-22)
To test:
1. Remove the relay from the compressor.
2. Use an ohmmeter set on the R x 1 scale. With the
relay held upright in the same position as it was
mounted on the compressor, place the meter
probes into the R and S terminal sockets. The
ohmmeter should read an open circuit.
3. With the meter probes still in the R and S terminal
sockets, invert the relay. The ohmmeter should
read a closed circuit.
Compressor Overload Protector
The compressor overload protector is mounted with the
starting relay, and is sensitive to the current load and to
the compressor temperature.
To test:
1. With the relay removed from the compressor, use
an ohmmeter set on the R x 1 scale.
2. Check across the overload terminals. The ohmme-
ter should show an open circuit.
Compressor
To test:
1. Remove the starting components.
2. Use an ohmmeter set on the R x 10K scale. Check
from each terminal (C,S and R) to compressor
housing. The meter probe on the compressor
housing should be placed on the grounding blade,
or in an area that is free of paint, such as a stub.
3. Next, set ohmmeter on the R x 1 scale. Test across
terminals R and C. The ohmmeter should read
approximately 2.5 ohms.
4. Test across terminals C and S. The ohmmeter
should read approximately 2.5 ohms.
5. Attach a 120 volt test cord to the compressor as
shown.
(See Figure 4-24)
If the compressor does not start, but an audible hum is
heard, replace compressor.
If compressor starts with test cord, but refuses to run
when the icemaker is operating, check for loose wiring,
a defective relay, or a defective bin thermostat.
Figure 4-22. Starting Relay
Figure 4-23. Compressor Components
Figure 4-24. Compressor Test Cord Connection
Starting Relay
Overload Protector
Screw
Sleeve
Terminal Cover
Washer
Washer
Relay
Assembly
Overload
To remove (See Figure 4-23):
1. Before removing the compressor, capture the refrig-
erant from the sealed system.
2. Remove terminal cover from side of compressor.
3. Disconnect electrical leads from overload/ relay
assembly.
4. With a a tube cutter, cut suction and discharge lines
approximately one inch from compressor ports.
5. Extract screws from corners of compressor, remove
compressor from unit.
Momentary
Switch
Circuit Breaker
Fuse
Compressor
Terminals
C
R
S