Fridge won't get cold on either AC or propane.

douggrainer,

Extreme cold may damage an absorption fridge, or cause it to stop cooling. Norcold makes an add on kit that can be used for protecting the fridge.

Again I refer you to Bob who had this happen. I'd suggest you read the thread under the full time forum on winter camping. Someone there posted the information about the Norcold kit.

I'm not suggesting that "burping" the fridge is a tried and true repair. It would be a last ditch effort, a desperation move.