My maytag MSD2756AEW will suddenly warm up, and when I pull the panel off in the freezer, its one huge ice block. I have previously replaced the start relay/overload trigger, and I am wondering if this problem is the defrost timer, and if it is how I can replace it. It seems to freeze up about every 2-3 months, and I have to manually defrost it.

This is obviously a side by side model you have. This is quite common in those models.

There are only 3 reasons a self defrosting fridge freezes over. They are:

1. Defrost heater faulty
2. Defrost limit switch faulty
3. Defrost timer faulty

You need to get a multitester and test each component for conductivity. Then you will know which component to replace.

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