jodeb720 wrote:
Thanks to all for the responses...
Mine hasn't died, yet - and I'm going on 12 years. I just think at some point I'm going to have to replace it - much like my dometic fridge (though I'll put a 12v compressor from jc refrigeration on my dometic shell when it does).
Many years ago professor95 took a 5k window AC unit and retrofitted it into a shell of a dometic unit he got from his local RV repair shop (the unit was dead).
It was quieter than his stock unit - and from what I remember, worked well for his needs. I often wonder why we've never improved the AC units utilizing off the shelf parts that are more efficient designs - and at a lower cost because the parts are off the shelf.
Enough ranting!
thanks again!
a single 5K window unit wouldn't cut it in larger RVs.
I have a 26ft TT that I gutted down to studs, removed the 1" R3 fiberglass insulation and replaced with 1" PolyIso which has a R rating of 7. I removed a 13.5K roof A/C and installed a 10K window unit in the larger open area in the rear of my trailer. Works fine for back of the trailer, not so much for kitchen and front bedroom.. So, I added a 6.5K window unit in the front bedroom.. Much better.
Compare that to my previous TT which was 20ft length, I was able to run a single 11K window air..
As far as "off the shelf" parts goes, the compressor and fan motors in RV A/C units are pretty much "off the shelf" parts. The parts that are not are the coils, they are specifically designed to fit in a very low profile case with a very specific design to allow the unit to have both non chilled and chilled air from the A/C to use the same 14" x 14" roof opening. Needless to say, their had to be a lot of compromise in performance to pull off this feat.
The compromises is what hurts RV A/C units efficiency. Proffessor95 pretty much proved that while you could retrofit a window A/C into the same box, it required a much smaller 5K unit to pull it off..
I built my A/C units into "cabinets" and they are not on the roof but rather on the sidewall and back wall.. On the outside all you see is decorative grill work and the window units do not stick out of the wall. Inside built cabinets which hide the A/C units.
The reason I went that route was the A/C unit was over 30 yrs old when I bought the TT, and while I was rehabing the TT may as well replace the old aged A/C unit.. The two window airs I used cost less than half of a RV roof air..
Best of all, so far has been able to easily keep the TT very cool even in 105F+ daytime temps in SC all on a 20A circuit at my relatives home :B
