Refrigerator Fix

I have a RP180 Rpod with a Dometic RM8501 model. I could never keep the fridge under 45-50 degrees. Been trying many things.When it's cooler outside, that's was the temp in the fridge, and being in Arizona in the summer,it's never cold.Here is what I did. Turn off the unit, and let it dry. On the left side inside there is a small white square that holds the T-stat. Take out the screw, and move that white box nearer to the top the top,under the freezer, slide it up the fin that hold it. Take a small piece of double sided tape, and fasten it to the back to hold it in place. The higher up it is, the colder it gets. Don't forget to put the screw back in the hole you took it from. The tape sticks on a dry fridge. My unit came with a fan blowing air up over the coils, so I added a fan on the top of the unit, blowing air out at the opening               Today is the 3rd day I did the project. The temp inside the fridge is holding between 36 and 40 degrees, and the temp outside today was 110 degrees. So I thought I would post this info, maybe it will work for you. I don't think I seen this info on the Forum. Good Luck.