Most of the problems regarding cooling issues when fridges are on the slideout are due to the vents being on the sides and not the roof. If the fridge is not on the slide the vent is on the roof. Remember hot air rises. So the cure many times is to add an additional fan on the back of the fridge to help move the hot air up and out. The therm.... thing was probably a thing called the thermister which is inside the refrigerator on the fins. It should be on the right fin and when you move it up (it should slide up and down) it will lower the temp in the fridge. If it off the fin of defective it will affect the cooling.
Just slide the clip higher on the fin.
I just double checked on that. The clip is shaped so that part of it wraps around the underside of the fins. It cannot be clipped further up. However, I am able to slide the thermistor up inside the sleeve in the clip. Would that be enough to make any difference?
I did call heartland and talked to the rep and was told that if its over a 100 degs outside that the frig wasn't going to stay cold. I have a log that we kept everyday with the temp of the frig and the outside temp and the temp of the coach. My last trailer's frig was always cold.
I believe that is the standard mounting for the 1350 series.