[Folkie]

I had what sounds like a similar problem 2 weeks ago while boon docking. We noticed a strong exhaust smell in the camper. When I pulled the upper vent cover there was a brown discoloration in the area of the chimney indicating improper combustion. I attempted to clean the burner twice but still had the same issue and now the fridge warmed up to 55 overnight with outside temp about 57
I could not get a good view of the whole burner to check the flame quality but what I could see looked ok. The only other thing I could think to do was try to clean out the chimney but didn't want to get too invasive while on the road. I was able to bum a very fuzzy craft pipe cleaner from another TM owner and fished it down the flue with some bailing wire after I let it cool off for awhile. It removed a lot of soot. After blowing out the debris it fired right up and overnight cooled down to 38 on a setting of 3.5
After we got home I bought a 3/4" boiler brush with wire handle 30". I pulled the cap and baffle out and ran the brush down a couple of times then gave the burner a good brushing and verified that the flame was good.
Then I went to work using a lot of foil tape and caulk to close off as much of gaps around the back of the fridge as I could reach. I case we ever have the problem on the road again at least we will not get smoked out!