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Parts for GE TCX22PACBWW Refrigerator - AppliancePartsPros.com

What was the original problem that prompted you to replace the defrost timer and defrost thermostat?
Did you check the defrost heater for resistance?

When you did this did you look at the evaporator coils.
If they were iced/frosted over to the point where the evaporator fan could not pull air through them then it was a defrost problem.
If they just had frost in one area (usually where the freon enters the coils) then it is probably a sealed system problem.
Both problems will cause the compressor to run all the time except when the unit goes into a defrost cycle.
Defrost is 35 minutes long and should occur every 10 hours. I do not have a wiring diagram for this unit so cannot say if it is 10 hours or 10 hours of compressor run time.

Is the evaporator/freezer fan running?
Is the condenser/compressor fan running?

I am assuming that the temperatures you give are the normal and the unit never gets down to 0 to 5 degrees F in the freezer.

Does the compressor cycle or is it on all the time?
You can usually hear it but should also be able to feel it vibrating.