It sounds to me like whoever installed the Amish cooling unit in October... did not do it right. There are two sealants that have to be put on the cooling unit BEFORE you shove the cooling unit into the fridge. They can be messy to deal with but they put a seal/barrier between the hot tubes in the Amish cooling unit from the fins.
That's a shame but not unfixable. I'd start by calling the place that did the work in October. Then if they would not redo it (take the cooling unit out...clean it up... put the sealant on like they should have done in the first place...and install it again) I'd call the manufacturer of the unit. You should be able to know who that is because they're the ones that you would call if the unit did not cool. It should have a warranty if it's truly an Amish Unit.
Find the serial and model numbers on the back of the unit. (Open the outside vent door and look for information.) Does it say PINES RV ??
Maybe it was bought through
David Force
901-337-9948
www.rvcoolingunit.com
www.rvcoolingunit.net