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Replacement parts for General Electric GSH25JSTASS Refrigerator | AppliancePartsPros.com

It is a GE with a control board so is a bit of a pain, just look at the number of GE units with control problems in this forum. Also GE likes to keep all tech info a secret so that does not help.

First you have to determine what is and what is not running.

Check that the evaporator fan in the freezer is running. It is required to pull air through the evaporator coils so it can cool it, also to circulate air into the fresh food section. You will see a sticky at the start of this forum about this problem.

Check to see if the compressor is running, you can usually hear it also you should be able to feel it vibrating and it should be warm.

If it is constantly running then you may have a defrost problem, remove the evaporator covers from inside the freezer so you can inspect the coils.
If they are heavily iced/frosted over then it is a defrost problem.
If there is just frost in one area (usually where the freon enters the coils) it is a sealed system problem. Note: This should be checked after the unit has run for several hours without a defrost cycle.

If the compressor is not running you may have a control or a compressor start device or the compressor itself problem.

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