Domestic Frig in New Trailer

Dometic uses a plastic clip on thermostat that attaches to the cooling fins. If this clip comes off of the fins or is not adjusted right your fridge will get too cold. Have you verified that the clip is attached and have you attempted to adjust it by changing its position on the fins?

Your fridge is probably OK. Gas refrigerators are different from home refrigerators. Gas refrigerators have no moving parts. Heat is extracted at the top rear of the cabinet (taking away heat makes it cold). The cold air is heavier and falls to the bottom settings up a natural circulation inside the cabinet. If you pack the cabinet solid the air cannot circulate which makes it very cold at the top and warmer at the bottom. Try rearranging the food and don't pack things so tight and you will probably be OK.

Or move those items lower in fridge

Area directly under the fins is the coldest spot.

Warmest spot is on door

Fan.