[tentcamper]

Im convinced that running the fridge on LP while traveling causes an in-efficient burn and soots up everything and leads to the rust. I think it is closing the shell and the fan running that changes the fuel to air mixture that leads to the in-efficiency and more soot and acids in the burn.

Our first TM, we traveled on LP and twice I had the issue within 18 months or each other. I switch to 12v and rewired so the fridge ran on the auto battery when traveling and only ran LP for camping without electric. I did not have a dirty burner after that.