Ben, I thought about your Amana when I saw this ad!
A few years ago, I had to add a small heater under the evaporator fan in my parent's 1998 GE Profile bottom freezer as the drain would freeze and the fan would stop as the water level would reach the blades. This model didn't have a drain heater but I think GE changed that on some newer ones because of this issue (at least that's what I was told). For some reason, it didn't happen in the first 5-6 years of service but happened 3 times in the few months before I repaired it. I couldn't explain why it was ok at first and not after a few years of use, maybe the insulation isn't as good as it used to be and it stays too cold after the defrost cycle. I know it was often an issue in older fridges...
Since I did that, never had a problem again.
It was a much easier job than replacing the defrost heater (not the drain heater!) in my 1964 Frigidaire refrigerator with one that was not identical (read not designed to go there!). On this fridge, the heater still worked but the element was grounded and I would sometimes get shocks when touching the chrome-plated handle or the bright trim around the cabinet or on the doors, even when the fridge wasn't in the defrost period.
Before I replaced it, I reversed the plug on the outlet so I wouldn't get get shocks while it wasn't defrosting (there was still no grounded cord on Frigidaire fridges in 1964 but I think the newer one in the ad should have one!).