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Parts for Whirlpool ET20PKXZW00 Refrigerator - AppliancePartsPros.com

See the attachment for your tech sheet.

You have to check what is running when it starts to warm up.

The compressor and it's fan are wired in parallel so when the fan is on the compressor should be on.
You can usually hear when the compressor is running but you should also be able to feel it vibrating. Getting warm is normal.

If the compressor runs all the time then it could be a sealed system problem or a defrost problem.
Remove the cover in the freezer so you can inspect the defrost coils.
If iced/frosted over to the point that the evaporator fan cannot pull air through the coil then it is a defrost problem.
If there is only frost in one area (usually where the freon enters the coil) it is a sealed system problem.

Be sure to check that the evaporator/freezer fan is running. It also should be on whenever the condenser fan and compressor are on.

Be sure to check this after the unit has run continuously for an hour or so. If you check the coil shorty after od during a defros cycle you will come to the wrong conclusion..

If it is a sealed system problem it will be an expensive repair as you need a pro. Often it makes more sense to putthe dollars towards a new unit.

If the compressor and it's fan are not running then it is probably a control thermostat problem.

If the compressor fan is running but the compressor is not it could be a compressor start device problem or the compressor itself.