I thought it might be time to post some info on my external air conditioner setup. We bought our Scamp 13 last fall and along with it came a new GE 5,000 BTU window air conditioner. The previous owners had built a shelf/bracket to mount it in the rear window as others have done. My wife and I didn't really want it up there right over the bed, so I investigated several othe options, most of which required cutting holes in fiberglass. Both here and on the Teardrops and Tiny Travel Trailers websites I saw postings about ground mounting the air conditioner and piping in the air, so that's what I settled on. I built an enclosure for the AC unit which essentially protects the part that would normally be inside the window, and provided a bulkhead to seperate the cold air output and warmer air return. The only mods to the AC unit itself were to drill a drain hole in the rear corner so I could be sure it is dumped out before repacking, and to reroute the power cord so it exits the rear of the machine instead of the front. I'm not sure I'd bother with this again. Definitely want the drain hole, though. The pictures should be pretty self-explanatory. All materials came from Lowes, except for butyl caulking that I put around the AC unit in the wooden enclosure, and some sticky stuff in a tube (one of the favored products on this site) that I used around the metal ducts to seal out the rain. After the machine itself is inserted into the box, I installed a metal strip across the back to keep it from sliding back out. All duct work is six-inch, which I would consider a minimum to reduce pressure losses. Lowes sells a six-inch flex hose which works great. Ideally, I'd have a larger return line (8" or so), since it's operating at lower pressure than the cold one being pumped toward the camper, which would come closer to matching the area of the AC intake. For this reason, and so I could bleed in some fresh air if desired, I added a fresh air intake on the front (a small register unit). The return line connection on the side of the box is removable for travel. I made a bridle out of safety wire that I hook to a spring across the front to hold it in place. This one is obviously not caulked in, but I don't really think that's an issue. I put a small drain hole in the front floor of the box just in case, though. Weather-proof wise, I tried to do everything so that water would have to go uphill to get in. Obviously, if we have a flood, there will be problems. I may end up making a slightly elevated mount of some sort.

So how does it work? On a recent trip to Asheville NC, it got into the 80s with high humidity, so we hooked it up. In no time, the trailer was much cooler and less humid. When we got back to Ohio, it was hotter, so I set it up in the driveway in 90+ degree direct sun and high humidity. Within a short time, the trailer was in the upper 70s. So far, all controls are original. Setup and teardown is easy. The warm air return connection at the top of the trailer is held in place by the vent lid. To install, all I have to do is lay the thing up there, then reach through the vent/escape hatch and put it in place. The cool air connects into an adaptor made from masonite that fits in the weather stripping in the back window. I "hinged" it in the middle with duct tape to make it easier to install and remove.

What would I do differently next time? I've thought about installing a 24V transformer to power a thermostat in the trailer that would switch the compressor on and off. (Both nights in NC, I had to go outside to turn off the AC.) Rather than go through the thermostat mod just yet, I'm going to mount a box on the panel that sits in the rear window that will allow me to turn the entire unit on and off. Essentially an extension cord with a switch in the middle of it. Next time, I'd be more careful with the fins on the back of the unit and maybe install an expanded metal grill across them. It already had some areas where fins are bent, and I added a few of my own. I've made a panel to put in place for travel at least. We need a deflector to send the air up a little higher when sleeping. We sleep with our heads at that end of the bed, so a little angle plate of some sort should solve that problem. This will be removable, though, so we're not sending cool air straight up to the return line in the daytime. Ultimately, I may connect the cool air line into some sort of register in the floor beneath the bed/dinette, which wuold probably make the air flow more uniform. What I have now with the masonite flange in the rear window was quick and dirty, but it's simple and works.

Okay, enough words. Here are some photos.

Parker

Here are some more pics. If you have questions, please don't hesitate to ask!

Parker

Well said, the roof vent return is a great idea.

That is one impressive piece of work there!

If your Scamp doesn't already have a name... I think you should call it 'Gemini'.

Click to view attachment

Thanks for a morning laugh! I'll tell my wife (Mission Contol).

Parker

Did you tell Mission Control that the name came straight from Huston?

Courtesy of President Johnson. I visited Cape Canaveral while in college during the Apollo days (did I just date myself?) and they were quick to point out that all that could easily have been built in and operated from Florida.

Yeah, I get alot of that "we have a problem" crap.

I'm glad that at least one person picked up on the pun, didn't mean to offend.

Way to go LT.

nice job.

Ace.

I've got to say, I think this idea could really take off. (sorry, I couldn't resist.)

I've got an '83 Casita with a window unit mounted on the floor. It's really good at cooling my ankles but that's about it. I've considered installing a roof AC unit but haven't done it yet because of all the bracing issues I would have to work around.

I like this because while I'm camping near home, in the Texas heat, I can bring the AC along in the back of my truck. When I take a trip to cooler climates I can leave the AC at home.

As an added benefit. I can reclaim some space for storage inside my trailer too.

Nice work!

Thanks, Bill! It worked great on our trip to NC this summer, and for our trip to Canada and Michigan last month, we didn't have to drag it along with us. I've since made up a switch mounted to the hose panel for the back window that allows me to turn it on and off from inside the camper. I think that's the 90% solution, rather than trying to install a thermostat.

Parker

i can imagine, me a tent camper, unhooking that long hose at night and running it to my front door in the summer heat. Ahh a good nights sleep.

neat boat a/c setup HERE
same idea.

How about placing one of these:

http://www.walmart.com/catalog/product.do?product_id=5402958

Where the furnace is. Of course you would have to have 110VAC to run it, but then you would have AC and heat.