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Replacement parts for FPE21TRW11 models | AppliancePartsPros.com

When you say it blows air, I am assuming that the evaporator fan in the freezer is running.

First check to see if the compressor is running. You should be able to hear it and feel it vibrating and it should be warm.
If not you may have a compressor starter/overload problem, a thermostat problem (not closing) or the compressor itself.

If it is running, remove the evaporator cover in the freezer and check the coils.
If totally frosted/iced over yo have a defrost problem.
If there the frost is very patchy or only in one area then you are probably low on freon.
If there is no frost at all either you are out of freon, there is a plug in the sealed system or the compressor is toast.
The latter two usually mean the unit is toast as repairing it will be expensive.

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

[COLOR="Blue"]If you are out of freon - is that easy to fix?[/COLOR]
No, you need a pro. First they have to find the leak and repair it. Then evacuate and refill the sealed system. It is fairly expensive and often makes more sense to put the dollars into a new unit.

[COLOR="Blue"]Anyway to confirm that is the problem as we have ice-maker unplugged - so not sure defrost problem is a possibility... [/COLOR]
If the compressor is running and there is no cooling either you have a plug somewhere in the sealed system or you are out of freon. Both are complex repairs.
Not sure what you mean by the ice-maker being unplugged, it has nothing to do with the defrost or the cooling of the unit.