[rdunk]

Quote: " I have unplugged the thermistor from the control box to see if it will default to constant run. I had the remote outside so the indicated temp is still dropping at this point".
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Keith, if your temp is still dropping, then I assume you are going to wait to see where it goes, before doing anything else. The thermister can go bad, because a service tech replaced mine.

On replacing the cooling unit, my cooling unit was replaced under warranty. Wow, that is a big job The fridge must be removed, to the outside, and everything on the back of the fridge is removed, the cooling unit is removed, the new cooling unit is installed, all of the removed misc parts are reinstalled, and then the fridge is reinstalled. After going through all of this on our fridge, nothing changed. It still did not cool correctly for us. I went through all of this to make the point that I think you are very smart to be "skeptical" about replacing the cooling unit until you know for sure.

I can't say for sure what made our fridge start working properly, but I think it maybe was when I moved the thermister in such a way as it (the end of the thermister wire) actually made direct contact with the fin. It works so good, I won't even take it off the fin to check it out. After two years of aggravation with our RV type fridge, it started working "ok" for us about a year ago, when in fooling with the thermister wire, I tried to make sure the end of the wire was actually touching the fin.

If I was going to have to pay for installation of a new cooling unit, at the prices you mention, I would (as you probably are too) give strong consideration to a new fridge, maybe even residential type. Probably not much warranty on just a new cooling unit either.

FWIW! And good luck with getting this fixed!