Defrost Thermostat - GE GYE18JBL Technical Service Manual

Defrost Thermostat

The defrost thermostat (over-temperature
thermostat) is located in the upper right-rear
corner of the freezer. The defrost thermostat
is clipped to the inlet line of the evaporator coil
to prevent a runaway state of defrost. The
thermostat will open when a temperature of
approximately 95°F is reached and close again at
approximately 65°F.
Defrost Thermostat Diagnosing
Check for an open defrost circuit.
J19 to J7 on Main Board
• J7 pin 9 (orange) to J19 pin 2 (blue): 33
ohms
If open, check the thermostat at the orange wire
at the 9-pin connector to the pink wire on the
defrost heater to verify the thermostat is open
and the defrost heater is not at fault.
Defrost Thermostat Removal/Replacement
1. Remove the evaporator cover (see
Evaporator Cover Removal, under
Evaporator Cover in the Freezer section of
this service guide).
2. Squeeze the sides of the metal retaining clip
to release the clip.
NOTE: The defrost thermostat can be replaced
individually or as part of the evaporator harness.
3. If replacing the thermostat as part of the
evaporator harness, unclip the evaporator
thermistor and defrost thermostat, disconnect
the 9-pin connector, 3-pin icemaker blower
connector, and defrost heater connectors. If
only replacing thermostat, proceed to the next
step.
4. Cut the thermostat wiring as close to the
thermostat as possible.
5. Strip the two wires back 3/16 inches for
splicing.
6. Prepare the replacement thermostat by
cutting the wiring 4 inches back from the
thermostat and strip the wires back 3/16 inch.
7. Using two bell connectors (Part #:
WR2X4686D), splice the wiring. After the
splices are complete, fill the bell connectors
fully with silicone grease (Part #: WR97X163).
Silicone Grease
8. Clip the thermostat to the inlet tube of the
evaporator.
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