All right experts, my rear A/C stopped cooling. I have never had a problem with them until the hottest day of the year. They are Dometic circa 1993. I can't find that they were ever replaced.
We have been using both front and rear A/C's in this weather and all of a sudden the bedroom A/C just started blowing warm air. I didn't hear anything unusual. I let it set for 2 1/2 hours to see if it was frozen but it still is not working.
I really don't know where to start to check it out. Any suggestions will be appreciated.
Kent,
Assume you have checked the thermostat.
If you can safely go up on the roof, remove the A/C cover. Have Peggy turn on the A/C. See if the compressor comes on?
If not, shut off all power to the coach and open the little access area on the A/C with all the wiring. Look carefully at wires, connections and at the capacitors. Check capacitors for oil leaks and swelling. Do NOT touch the terminals of the capacitors, even with power off until touching an insulated metal tool (regular plastic handled screwdriver) to both terminals of the capacitor to discharge it.
Brett
Brett, thanks a lot. That's the kind of info I was looking for. Its been ages since I messed with an A/C unit and that was a residential central air unit.
I checked and cleaned the thermostat switches. The blower comes on just fine but the compressor is not coming on. I presume the box enclosing the capacitors you described is up on the roof near the compressor and its too hot to go up on the roof today. I will do so in the AM and its a nice cool 90 degrees. Should I find a leaking capacitor I can just replace it but is there any other cause that might be as simple?
Corroded wire terminals and bad capacitors are the most likely, though of course it could be a failed compressor. But, generally when a compressor fails, it locks up and trips the breaker, so no air flow as the fan has no power either.
Brett
Brett, that's kind of what I was thinking. I'll check everything out in the morning.
Kent,
If above suggestions fail, you might try and find a RV AC forum with a section for troubleshooting and/or give the manufacturer rep a call. Bummer in the heat! Probably a lot of shops in the Norman/OK City if everything else fails. 1993 is a long time for a roof air without any trouble. Might also check online to see if there are any service ports where you could check pressures but R12 is only AC shop available, at least here in CA.
Have not tried out two on the front sofa.
Well, I got brave and went up on the roof in this heat. I wish I hadn't. There is yellow oil around the evaporater and on the roof. Looks like the thing sprang a leak and all of the freon is gone. All of the oil is back by evaporator none up by the electrical box so I'm pretty sure it's not blown capacitor.
Seeing that the unit is 18 years old I think I should just replace it but I want to keep the custom painted shroud and the diffuser on the ceiling. I would also like to put in a heat pump. Has anyone with a similar coach upgraded?
Steve Hill just installed 2 15K heat pumps.
If you cannot match the shroud, you might just consider replacing the whole thing with a newer version:
I found a 2000 GV320 40' with a SLIDE! 28,000 miles for $100,000. You're probably tired of that two-bit paint job anyway! ;D
for those of you interested, check this out:
2000 Foretravel Grand Villa GV320-Class A RV-Rutherfordton, NC-RVSearch.com (http://www.rvsearch.com/findrv/index.cfm/a-d/tc-36261/vid-623062/)
Trent
Man that is a beauty but it has a slide and its white. Actually, I can't imagine a coach I would like more than ours. The only things not new on this coach in 2009 are the fridge, the A/C's, furnace and water heater. I can replace them all for a whole lot less than $100,000.
Kent,
When we went to pick up our U300, the fridge had just stopped working. I had a new Norcold in our garage at home so the seller installed a couple of Duo Therm Quick Cool roof AC units. They have digital thermostats and have a nice clean white interior diffuser. The two really pump out the cold air and we have really been pleased with them. Our old Southwind has a Dometic AC but in comparing the two, the shroud is not as tall and I can't imagine an interior diffuser fitting different brands. Unfortunately, I think you may be limited in your options here. A Dometic rep would be the next call for his suggestions.
Steve Hill, Are your 15,000 btu roof air conditioners low profile? Do they have the side shroud vents? What is the model number?
Anything have to be modified to convert from 12,500 btu to 15,000 btu?
Kent,
Not to pour salt on your wound but we have an inch of rain forecast tomorrow with snow 45 minutes away on Donner Summit. We may be broke and the Dodgers bankrupt but we still have the weather (and fires).
Pierce, do you know if your new A/C units are 13,500 or 15,000 and are they heat pumps?
Be careful, you may end up with two 93, U300's in your driveway. I've been looking for a place with better weather. I'm sure our puppies would enjoy a romp together.
Re the Grand V for $100k I just looked in my NADA wholesale book and according to it that unit with 1 slide is listed for $118900 wholesale and retail $154080. So looks like a good price for someone.
Be very careful with NADA price guide. PM if any questions. They do make a great deal of mistakes.
Not saying this coach is not priced aggressively.
Kent,
After you check the capacitors as Brett Wolfe suggested, you might consider the circuit board, which is under the metal cover. There are several screws that have to be undone to get at the board. The board on my '92 Dometic (Duotherm) A/C went out last November. I was fortunate to be able to buy the exact replacement from Gary Bouland who had to replace his entire unit before he could use the circuit board. Dinosaur makes replacement boards for that A/C. You just have to figure out which one is appropriate. My symptoms were different: unit came on without me turning it on, wouldn't shut off. Relays were stuck.
Perhaps someone more knowledgeable can figure out a way to test the compressor first before investing in a circuit board.
Kent said: "There is yellow oil around the evaporater and on the roof. Looks like the thing sprang a leak and all of the freon is gone.'
Sorry, Kent, please disregard my email re: the circuit board; you have bigger problems.
Kent, you never never want to go up Pierce' s drive in you motorhome. I just barley made it in my '2002 Mazda pickup
Kent,
Both of my roof airs are 13.5K BriskAir not heat pumps. They both have the heat package (heat strips) but they only put out warm air, not really hot. Both were installed with the Comfort Control Center, a nice touch with illumination for x seconds when you touch the control.
The 13.5K works great aft but bigger is better forward. Heat pump would be good if connected to cheap juice. We are usually on BLM land or campgrounds so propane is the heat source.
I do have a source for $1.99/gal propane nationwide and will put up a post on how to get it at this price (you have to have it at home).
Attached are what the unit looks like on the roof and the control center.
The latest new models use 410A rather than Freon R22 (mine is the old style).
Thanks Pierce! Mine are the Penguins. The rear is 13.5. I think the front is 15K.
I have read in previous posts that the A/C's with 410A don't cool as good as the ones with R22. I don't quite understand that. If a new unit is 13.5K then it seems it would have to have the same cooling output capability as an old 13.5 unit with the R22. I guess I will find out. I'm planning to order a new 13.5K Penguin today. I have been told by the factory and two local dealers that there is a direct replacement for my unit. I will be able to use my old thermostat, plenum and shroud but I have to stay with13.5K.
Any comments on new A/C's with 410A vs. old ones with R22?
Freon is probably the most efficient refrigerant today (or should I say, yesterday) but is not compliant (in this country) because of the CFC regulations. You probably remember when all the retro kits came out to convert cars to R134a. Easy to change over with just a couple of red and black (I think) fittings but not as efficient. Ice cold air was replaced by semi-cold air, a big deal if you lived in Phoenix. I suspect that 410A vs. R22 is the same story. Propane is even starting to be used in the place of R22 in some cases. For a good primer about refrigerants, go to: http://en.wikipedia.org/wiki/Refrigerant (http://en.wikipedia.org/wiki/Refrigerant) In short, R22 has had it's time and is going the way of the dinosaur.
Hey, bring your dog and come on out! Don't let Bill scare you about the driveway. Have had a couple of people stall (in cars) and then back over the edge. Had to pull them out with the tractor.
Bill, Gaylie and I just had to laugh again at your profile photo. Love you sitting at the table with the drink close to the camera!!! Great!