Diagnosing and replacing faulty fresh food thermistors in GE dual evaporator refrigerators
Proper diagnosis and repair is crucial on these models to eliminate probable repeat calls!
Failure of the fresh food evaporator thermistor can cause many symptoms, some of which could cause intermittent operation. These symptoms may include the following:
- Uneven temperatures in both the fresh food and freezer sections
- Iced-over fresh food evaporator (no defrost)
- Intermittent long shut downs (poor cooling)
- Excessive moisture in the fresh food and freezer sections
- Clumping of ice in the ice bin
- Poor ice production
If the fresh food evaporator thermistor is determined to be defective, it’s essential that certain precautions be taken for proper replacement to avoid a repeat call in the future.
Materials required for proper replacement:
- Silicone grease (WR97X163 or equivalent)
- RTV102 sealant
- Bell Connectors (WR2X4330D or equivalent)*
- Aluminum Foil Tape (WD49X27 or equivalent)
- Two Wire Ties (WR02X11607 or equivalent)
After removing the evaporator from the rear wall of the fresh food section, reach around the back of the evaporator and pull the thermistor out of the thermal block. Do NOT cut the wire tie holding the block to the evaporator.
Prepare the replacement thermistor:
1. Fold over a piece of electrical tape onto the thermistor wire; position it half an inch away from the thermistor head. This will allow for proper positioning of the thermistor head when reinserted into the thermal block.
2. Fold over a four-inch piece of foil tape (WD49x27) onto the thermistor wire; position it behind the electrical tape. This will protect the thermistor wire from cuts and allow for the formation of a drip loop.
3. Insert the thermistor into the thermal bock until the electrical tape touches, and then bend the foil-taped wire at a downward angle to begin a drip loop beyond the edge of the evaporator.
4. After forming the drip loop, wire-tie the thermistor harness to the bottom existing wire tie on the side of the evaporator. Splice the wires using the entire length of wire provided with the replacement thermistor. Use the remaining thermistor wire to form a loop with the wire splices facing upwards. Wire-tie this loop to the evaporator top wire tie.
5. Apply RTV102 where the thermistor wiring exits the thermal block. This will hold it in place and completely seal the splice connectors with the silicon grease, making sure the entire connector is moisture resistant.
6. Upon completion of the repair, inspect the fresh food evaporator fan motor. If there is evidence of corrosion where the wires enter the fan motor, replace the motor or assembly.