Dometic AC installation

[TomWoodson53]

I am restoring a 1977 Sovereign and am replacing the A/C unit. I purchased a Dometic 13500 Brisk 2 with the drain kit. I am having trouble getting it installed properly since the molding/weather stripping provided is flat and obviously the roof is curved. I called Dometic and they had no suggestions. I have the same problem inside in that the flat metal plate that installs against the ceiling is flat and the ceiling is curved. When you tighten the screws is creates a flat area on the roof which has gaps and will certainly leak. Am I supposed to try to trim the molding to match the curve on the roof?

As always your kind help will be greatly appreciated.

Tom

[Belegedhel]

When I installed my new AC, I bought the plastic condensate drip pan that AS used to use in their AC installations. This is a plastic pan with a curved shape to it that the AC sits in on the roof. The condensate drips into the pan, and the pan accumulates it and funnels it into a nipple that the condensate drip tube is attached to. There is now an alternative available that is essentially two cups that attach under the AC drip points. These cups catch the condensate, and then run it through the double foam gasket that will be under the AC, to meet the condensate drain tube. When you say you have a drain kit what does yours look like?

I also made two wooden inserts that match the curve of the inner skin and outer shell and inserted them between the skin and the shell in the front and back of the mounting hole for the AC. I used hard wood that was about 1.5" wide. This is not there to provide weight bearing support, but to give the mounting bolts something to clamp against, rather than just squeezing the inner skin and outer shell together, and to maintain the curve of the roof. Yes, the metal plate that is used on the inside is still flat, but with the wood supports, it doesn't cause a flat spot in the roof.

My plastic inside ceiling unit does not fit tight against the ceiling, since it is designed to fit agains a flat roof, but the gaps aren't obnoxiously large and don't bother me.

good luck!

[Jammer]

The only A/C "replacement" I've performed was the removal and reinstallation of the a/c on my Cayo, to allow me to correct some leaks (Due to exceptionally sloppy work on the previous a/c replacement 20 years back). My roof is essentially flat in that area.

The usual recommendation for exterior sealing trailers with curved roofs is to use two foam gaskets instead of one. There is enough give in the gaskets that they will then seal. It isn't necessary to cut the gaskets to fit the curve, and the foam is hard to cut smoothly, so it's best to leave them. I would recommend getting one-piece gaskets rather than the four-piece ones that you assemble.

I'm not sure what the usual advice for the interior is. Did you have a similar A/C installed in the same location previously so that there is already a reinforced 14x14" hole? If not you have some reinforcing to do.