My neighbor in Texas park has a fridge problem. Model RM 2852 Dometic. Stopped working during the night while connected to A/C. Switched over manually to LP and waiting to see if it will cool. The flue above the LP flame where the heater element is for 110 is really hot to the touch, but the cooling tubes are really cool on back of fridge. Any ideas as to what to check? We checked the fuses and they seem to be ok. Lights on control panel seem to be working ok. Lp came on and no check light came on. Fridge is 3 years old. Guidance is needed quickest. Tks in advance.