Roof Top Air....

GoneCamping · 09-18-2006, 10:17 PM

Anyone install a roof top a/c unit in your bus? I've got one and want to get it installed soon, but I'm curious about the alignment and support. Seems to me it would be easiest to install it beteen the cross members, but I'm curious if there will be enough structural support like that, as the A/C is VERY heavy. The other option is to cut through one of the cross members, but this seems more difficult and I don't want to compromise the structural integrity of the roof. Mind you, I have no perceived problems with this, and not concerned about reducing 'roll over safety' as that is not my conern...I just don't want the thing sagging, or worse yet developing a leak....

Any input would be helpful...

lapeer20m · 09-19-2006, 09:15 AM

i want a rooftop ac unit! let me know how your install goes for ya

GoneCamping · 09-19-2006, 08:42 PM

I still have to get the thing working before I try and install it. I got a donor 5th wheel and it had this ducted Coleman air on the roof...or what was left of the roof of the trailer. Anyway, the fan motor is locked up tight, not sure about the compressor yet. I'm going to put it in anyway even if I never get it running, if for no other reason than to have the hole already cut, the ducts already figured out, and the electrical already run.

However, I do want to try and get it working first....that sucker is HEAVY!

The more I think about it, it will have to go between the roof ribs, as the duct's will have to feed off the sides and come down inside the ceiling area...something I'll have to fabricate to make it all work. Would have been simpler if I had got a direct blow type of A/C...

I'm still worried about the weight of this thing and the relative ease of the metal to flex once the 14" square hole is cut. Will be hard to reinforce it on the sides since I gotta run ducts out the sides... hmmmmm

lapeer20m · 09-19-2006, 09:08 PM

Quote:

Originally Posted by GoneCamping

I'm still worried about the weight of this thing and the relative ease of the metal to flex once the 14" square hole is cut. Will be hard to reinforce it on the sides since I gotta run ducts out the sides... hmmmmm

from a guy who once cut a 9 foot hole in the side of one bus, and removed 12 feet of roof from another, I really wouldn't worry about a 14" square hole. bus roofs are incredibly strong.

captainkf · 09-20-2006, 12:01 PM

Your roof should support it no problem. I have seen full size 13,500 btu units mounted in the roofs of tent trailers. Place your hole close to a rib, but don't cut through it if you can avoid it. Shim the space between the outer and the inner skin of metal with wood so that the edge of the ac unit gets support from both inside and outside skins. Then use foam strips to create a grommet around the top outside edge, the edge the AC unit sits on. These machines are designed for flat surfaces, not the convex curve of our roofs (or airstreams). The ac manufacturer does make a grommet for this purpose, but thick weatherstripping with the adhesive on side works well also.

-Richard

the_experience03 · 09-20-2006, 04:08 PM

If the roof can support 20 people as mine has done, I'm sure it can support the A/C. My recommendation would be to leave a little space...let things move instead of trying to make everything rigid because you're not going to. I guess what I'm saying is use lots of silicone or caulk.

TomCat · 10-01-2006, 02:21 PM

I installed 2 Colemans on the roof of my Thomas. No problems so far.

Jay

http://jsbird69.zoto.com/user/lightb...aded-desc/0-90

Ryan Grimm · 10-02-2006, 09:02 AM

Last year I saw two Coleman units out of a late 80's RV, the boneyard sold them for $50 each with the usual 50/50 guarantee....50 feet or 50 seconds, whichever came first!

No, really, I checked them out for the guy; we pulled them, hooked them up temporarily with a heavy extension cord and plugged 'em in to run. Ran fine. For $50 each and new gaskets, he was good for under $200 total.

I keep telling everybody, haunt boneyards, those folks have NO idea what stuff is worth. Bought a small RV 3-way fridge for $20, they give away stuff.
19-foot awning (a nice one) for $50.
Got another 30 gallon fresh tank for free a few months ago.

Also, keep an eye peeled on Craig's List in your area, just ask on the WANTED list for a trailer/RV you can pull the goodies from...got everything but the toilet from a 32 foot fifth-wheel last year, for the effort.
And ask if you can pull the stuff out of a trailer being junked.

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