While researching the "how-to's" of installing a A/C in the closet of my 1983 13' Scamp, I had called the Scamp Factory and talked to the parts manager. According to him, Scamp quit installing A/C's (in the closet) a few years back. They quit, according to him, because of the additional work needed to get proper venting, the loss of storage space in the closet because of the unit and all the needed ductwork, and having to modify each A/C to get outside air to cool the condenser. Despite all the modifications, they were getting many service returns on the A/C's due to overheating,(some AC Brands were more suseptable.)
Additionally, it was just easier (and cheaper) to add the additional support structure necessary for a ceiling mounted AC Unit during the manufacture of the fiberglass body, than it was to perform a closet refit, and the celing units were designed specifically for the use...no modifications necessary.
Scamp did use 5000 BTU units in the 13' trailers in the closet install, any more is too much for the sq. footage of the cabin.
Despite all that, a closet mounted unit works fine as long as three things are strictly met:
1. Plenty of outside air to cool the condenser.
2. Good drainage to the outside of the trailer for any condensate.
3. Complete isolation of cabin air from outside air.
The biggest problem for closet A/C's is not getting enough outside air to the coil. Generally, a factory install has the outside air intake above the exhaust. Cooling air is drawn from above the unit and down. A hole was usually cut in the A/C units outer case on top to get more air in to pass through the coil. Consequently, the lower portions of the coil got the least amount of air. Check the lower left side wall inside the closet, (the closet wall closest to the dinette) for signs of excessive heat, that's the side of the condenser coil furthest from the compressor pump and usually the hottest part of the coil. If there is not enough outside air reaching that area to wick away heat, the coil may become damaged and fail.
Up until recently, it was hard to find window A/C units small enough to work properly inside a confined space as narrow as the Scamp Closet. I installed mine only because the unit was narrow enough to allow an air gap on both sides for air to reach the sides of the case.
If you remember to keep the trailer door, vents and windows
shut tight when you run the AC, periodically check for any excessive heat problems around the unit, and be sure the condensation drain is working, a closet AC will keep you cool for a long, long time.
My homemade install is working fine. If you'd like to see how I done it, check out my photo slideshow...