Pulled Perry's thread up because I'm starting the same type of project. Photos of the aluminum baffle which I fabricated and the huge, open chamber in which the fridge
mechs reside follow. I intend to attach the baffle by replacing sheet metal screws in the upper side of the lower access door and thru bolting. The <1" pinch in the air column will come just below the upper condensation fins. The Bryant RV link mentioned above suggests that the furnace
should be level "with the top of lower opening." I assume this means the mechanicals as the fridge
body rests on the floor of the trailer. The mechs are roughly on level with the lower access door but no attempt was made to close off the "sump" below the stool upon which the mechs are mounted. Installing a sheet metal plenum to close off some of this space below, beside and above the mechs is not a simple task and requires removing the fridge
box and mechanicals. I'm not willing to do that yet so am wondering what "insulation" I should use to both plug air leaks
and also reduce the volume of this space. Is aluminum faced glass batt insulation an acceptable material. I assume there is some fire hazard in the area around the percolation coil. I'm going to use a 120vac muffin fan initiallly, perhaps buy a couple 12v if I get better performance than in the past. I realize that I may have a number of problems, dirty flue, badly adjusted flame, no "hot weather" resistor pigtail in the thermostat line, faulty thermostat. This fridge will cool acceptably on 120vac but immediately shuts down and warms up again. The propane
maintenance problem is on the back burner UNTIL I get a positive indication that the fridge will function on electricity.