Community Forums

Radioman · 03-05-2022, 11:30 AM

The dash air on our 2008 Mountain Aire has a leak someplace and we and several techs can't seem to find it. We've had it completely checked with dye and sniffers twice -- from the compressor to the dash outlets including the pipes under the chassis -- with no luck. We have to add freon every 6 months or so to keep getting cool air. It's expensive and aggravating.

Do we need a whole new system ($$$)? Anybody else had a similar problem?

Thanks in advance for any wisdom.

deandec · 03-05-2022, 01:32 PM

1. Do you have the Over The Road rear dash AC system in your bedroom?

2. If so, did the techs test those AC hoses and connections?

3. Soapy water sprayed on the hose and connections seems to be a very successful DIY way to search for AC leaks.

Did you get a cost estimate for replacing the dash ac system?

BrokeDown · 03-05-2022, 06:33 PM

Quote:

Originally Posted by Radioman

The dash air on our 2008 Mountain Aire has a leak someplace .

Same coach, same problem. I hope you find out what it is.
-B

Calpop45 · 03-05-2022, 10:05 PM

Lot of this going around! Same problem on a ‘18 DS solved by pressurizing the system to 300 psi with nitrogen. Soap solution revealed a small leak at the compressor shaft after pulling the drive belt and clutch assembly. New compressor and dryer equals problem solved!

ThunderRidge · 03-06-2022, 04:31 AM

No dash a/c on my coach as well. Cummins recharged the system and added dye. The recharge lasted about two weeks and so far can’t see where the dye leaked from the system. The lines must be well hidden, and I don’t feel like trying to find the leak. When it’s warm I am always running the generator and all 3 roof air conditioners.

Dutch Star Don · 03-06-2022, 11:23 AM

This is such an ANNOYING and costly issue. On our 2014 DS, they checked and refilled the dash A/C once under warranty and then it failed/leak every few months after that. I knew that every summer it would need freon. I eventually located the leak by accident. Just behind the driver's side tag, is your side radiator and A/C condenser on the bottom of the radiator.

If you pull back the mudflap behind the tag that prevents debris from being thrown onto the radiator, there are two A/C hoses going into the condenser, one on top of the other. It was obvious that one was leaking at the hose end/connection, as evidenced by a slimy mud on the fitting.

There is an aluminum fitting that is threaded on both ends that threads into the condenser, using an O-ring to seal the connection. The A/C hose threads into that with an O-ring.

I removed and replaced both O-rings and had the system recharged, it worked for a while and then the compressor froze. I replaced the compressor and pulled that hose. I had an A/C shop put a new end on the hose and recharged the system. Once again it held pressure during the leak down test.

I eventually sold the coach and heard eight months later the system had leaked again. To this day, I believe that double threaded fitting that screws into the condenser and then the hose screws into it was machined wrong.

Sorry for the long post but just something to check.

ThunderRidge · 03-06-2022, 05:52 PM

Thanks Don. Great post. I will check it out at some point, but pretty much resigned to just running the generator and roof airs in hot weather as I always have. It seems to be to much trouble and expense to repair.

Calpop45 · 03-06-2022, 11:09 PM

Seems to me that a nitrogen pressure test by a competent tech would go a long way towards remedying this “annoying” complaint. $175 on the west coast, some leak detection fluid, and you’ll know what’s happening. Just sayin’

ThunderRidge · 03-07-2022, 04:56 AM

Quote:

Originally Posted by Calpop45

Seems to me that a nitrogen pressure test by a competent tech would go a long way towards remedying this “annoying” complaint. $175 on the west coast, some leak detection fluid, and you’ll know what’s happening. Just sayin’

Cummins already went that route for me. Problem not solved. Competent tech may be the key word.

Radioman · 04-06-2022, 09:32 AM

Quote:

Originally Posted by Dutch Star Don

This is such an ANNOYING and costly issue.

If you pull back the mudflap behind the tag that prevents debris from being thrown onto the radiator, there are two A/C hoses going into the condenser, one on top of the other. It was obvious that one was leaking at the hose end/connection, as evidenced by a slimy mud on the fitting.

Thanks Don,
That's exactly where we found our problem. Clearly a leak from one of the hoses. Why the professionals couldn't find it is beyond me. We'll get the hose end repaired as you suggest. Now we are contemplating replacing the compressor and drier as well for safe measure as they are going on 14 years. I appreciate your insights.
Joe

10 fan · 04-06-2022, 09:58 AM

Mine leaked out last year, had it checked and they could not find a leak with dye. Said it holds vacuum and charged it. Lasted 3 months. I bought the tools and charged it myself with dye. Lasted 3 months. The leak must be in the frame channel. I bought the sniffer and a uv light but no luck.
Thanks for the tip (DSD). I did not check there only the condenser.