I have an Amana ARB9059CS bottom mount freezer refrigerator. About two weeks ago, it iced right up. I took the back panel off and defrosted everything. The drain to the drain pan was not plugged, and the melt water drained fine.

I tested the defrost timer, the defrost thermostat and the defrost heater and everything passed. The timer was advancing, the thermostat was closing when cold, and the heater showed 32 OHMs. I also burned my finger when I touched it during a defrost cycle!

I figured it must be the timer, so I replaced it, and about a week later everything iced up again. I retested the components, and they all still appear to be working properly.

My only other thought is it could be the thermostat on the threshold of failing? Should I just replace it anyways?

Thanks, Denman. I, too, can't see the heater going intermittent. From what I know, they usually just burn out. I also can't see having two bad timers!

I hope the repair shop will take back the new thermostat........

You were right. They would not take back the timer. I replaced the thermostat, and the fridge has been working good as new! Even though I have an extra timer, it was still a much cheaper repair than calling in a technician!