1. It is NOT the size wire gauge for SAFETY. It is the SIZE wire gauge to adequately transfer FULL 12 volt power to the refer. The smaller the wire gauge the LESS 12 volt power is transmitted to the 12 volt element.
2. You have as BYPASS tstat. That is why it freezes on 120 and cools correctly on LP. The POINTS in the 120 side of the tstat are welded/stuck together and the unit runs 24/7 on 120. You need a new tstat to fix the 120 problem. IF you have a silver metal capillary tube inside on the evap fins the tstat I linked too is the correct tstat. It is a 120 and LP ONLY tstat
3. Regardless of what the OEM did does NOT make the original install correct. Chinnok motorhomes were about the same size as yours and their Dometic 3 way refers had 8 gauge wire to the refer from the battery.
4. While some 3 ways do have a tstat on the 12 volt side, that does NOT change the fact that the DC element is NOT for cooling down, only maintaining existing cold while in transit.
5. I doubt the element sleeve has come loose. That is extremely rare, I have only seen 1 in 38 years. Doug
Your model does have the 12 volt thru the tstat, but this is what the instructions state. Doug
DO NOT operate the refrigerator on 12 volt when the vehicle is parked. The amperage draw of the 12-volt DC heating element can discharge a battery in a very short time. The installation of a 12volt DC operated refrigerator requires a relay to be installed on the tow vehicle or in the caravan. The relay will automatically shut off the 12 volt DC power to the refrigerator when the ignition is turned off.
