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Replacement parts for WHIRLPOOL EL87TRRRS00 Refrigerator | AppliancePartsPros.com

First you have to determine if the compressor is running. It should be warm, you should be able to feel it vibrating and usually you can hear it.

If not running.
Try turning the defrost timer cam, you may be stuck in a defrost cycle.
Try rotating your temperature control to see if it will come on re: the switch contacts are sticking open.
If no go unplug the unit and check the thermostat with a meter to see if the contacts are closed.
You could try unplugging the unit, shorting the two wires at the thermostat together and taping them so they cannot short together, Then plug it in and give it a try.

You may want to start by checking for power at the compressor with a meter.

If compressor is running.
Check that the evaporator fan is running.
Remove the evaporator cover so you can see it.
If the is no frost or just frost in one area or it is blotchy you probably are out of freon or low on freon or the compressor is toast
All will be an expensive repair so it is probably best to put the dollars toward a new unit.
Note: Make sure the unit has run several hours before doing it as if you check it just after a defrost cycle the coils will be clear.

If the coils are heavily frosted/iced over, you probably have a defrost problem. Possible causes are the defrost heater, the defrost thermostat or the timer itself.

Following are a couple good sites with basic fridge repair info.
http://www.applianceaid.com/frig.html
Refrigerator Repair Guide: How To Fix a Refrigerator - ACME HOW TO.com