How to make an old refridge ROCK!!
Well, we're talking about a 1978 TT (Excel) with the original Elixir refridge.
I moved this over from appliances as I thought old TTers might be interested in it. I hope that is OK with the moderators
Everything works great although I did replace the furnace last year.
This year it was time to replace the floor of the refer as it was 3/8 particleboard and it was turning to sawdust as the refer was falling through it. After disconnecting all the wiring, gas line and hold down screws, it was fairly easy to slide out and place aside.
In looking at the cabinet I noted that there was only about half the depth of the refer that had any fiberglass insulation on its sides and none on top. Also noted was that there was about 3+ inches between the back of the refer coils and the back inside of the cabinet without the air baffle needed to cut that down to 1" or less of the coils for proper "chimney" effect of the cooling air coming in the outside vent panel.
Lots of dust, dirt, rat droppings, etc. were vacuumed out of the area and all the insulation was removed. The floor literally fell apart as I pulled it up. I had some exterior OSB board of the same thickness available so that was cut to size and screwed in and then all the edges were sealed with caulking to prevent carbon monoxide or leaking propane from passing into the TT living area. This is something many may miss in working in the refer cabinet.
I then lined (to the full depth of the refer sides) the cabinet sides and top with 3" of fiberglass insulation (held in place with upholstery spray adhesive). A new seal was placed on the refer front flange where it meets the cabinet wall as it slides in (normal foam weatherstrip). There is also at the top of the cabinet a required wood baffle coming down from the inside roof to with in 1/4 inch of the refer top to form a "no more than" 8" wide chimney out the top exhaust vent hole.
All these required items came off a Dometic vent installation .pdf from online sources. It may be an Elixir but it's still a gas absorption refer and they all work the same way.
At this same time I elected to remove the old pie fan that someone else installed blowing up from the bottom of the coils (old and high electric draw) and replace it with 2 very low wattage pie fans up at the top of the chimney so they suck out the hot air. I had to fabricate a couple of brackets to mount them and I used a thermal switch inline with the power lead to control them. There is also a fan inside the refer on the cool coil that is tied to a switch inside the TT that also controls power to the 2 fans up top when the thermal switch closes. You can see up top where water had gotten in at one time but it is all solid up there and visually inside the cabinet so it can't be seen in the TT.
In the last picture you can see the lower air baffle that meets the bottom coil of the refer and the placement of the top fans. Once all was ready the refer was slid in and everything connected back up. Gas connections leak tested. Now would it all work?
Turned on the gas and lite the fuse, er., burner :-) Seemed to work so I let it sit all night set as cold as it would go with nothing in the box. In the morning it showed 26 degrees in the refer section and the freezer was cold, really cold. The night never got below 80 degrees outside (ya, I live in the desert!).
I let it run all day with the TT closed (no ventilation just to see how it would react with a very hot exterior (102) and a very hot inside TT (103). It warmed to only 43 degrees. I'm satisfied with a 60 degree DELTA on the temperature.
Surrounded by 103 degrees and it still cools to 43? That's good enough for me and for a 38 year old refer!
Things to take away if you have trouble with your refer-
Make sure it is insulated top and sides as much as you can inside the
cabinet to the full depth of the refer.
Make sure the chimney is built properly per the instructions.
A VERY BIG ITEM- make sure you have an air baffle at the bottom rear
designed the correct way so cool air goes thru the coils and not around
Make sure the TT or coach is level according to the freezer bottom.
Last item, make sure you have a good flame. Mine didn't at first and I
traced it to having an inline gas filter that was clogged. As no filters were
available anymore I had to remove it and bypass with a brass pipe.