Dash Air Recharge

[SLSettles]

My dash air was working sporadically last year when we bought our 2004 Revolution (by Fleetwood model 40D on Freightliner chassis, side-breathing radiator with Cummin ISC diesel power plant... cause I know someone will ask ;-)   It would blow cold for a few minutes after starting and then peter out. But now it is warm from the start. I know that I might have multiple problems. A tech told me the initial problem sounds like heater air is mixing with the cooled air, so it only blew cold until the engine heated up. But I suspect that the lack of any cooling now is likely due to lack of refrigerant. I am considering purchasing a vacuum pump and manifold set so that I can properly recharge the system myself (the equipment is about the price of an hour at Cummins-Atlantic!). My main concern is that the low-point cap is at the front of the coach and the high-point is at the rear, so obviously the manifold hoses cannot be plugged into both at once. How should I go about drawing-down and refilling the system? Or should I hang it up and pay Cummins?

[desertdeals69]

I would just add to the system a can with stop leak and see if that helps.  Usually the system is sucked down after the system has been opened, such as replacing o rings or hoses.

 

[SLSettles]

I may end up doing that, just don't want to find out down the road that it's the equivalent to using Fix-a-Flat or LiquidPlumber... doesn't really work and makes proper repair later more difficult.

[hermanmullins]

SL,

Most times when you are having your A/C serviced the tech might add a can of Freon with a stop leak added. Fix-a-Flat is item used to get you to a location where you can have your flat repaired, however it is a mess to clean out of the tire. Liquid Plumber is not for stopping a leak it for clearing a clog in drain pipes. The one thing about Freon with a stop leak additive is that it is in constant motion through the system and is not intended to stop a massive leak but to help with a slow leak that is almost undetectable.

Also you don't have to go to Cummins to have your A/C serviced, most any automotive a/c service center can do it for you.

Good luck and hope you are able to get cool soon.

Herman 

[dave111451]

As someone  who has had to clean sealer out of ac  systems on farm equipment I would not advise using it.Plugs expansion valves orfice tube etc.

JMHO                                                                                                         dave

[manholt]

SL.  In the meantime run your roof AC's of the generator as your traveling down the road!

[tcolburn]

Had the same problem with dash air on our '04 Revolution 40C. Our local friendly car mechanic checked it, found the refrigerant was low, and added some more. Dash air has been working fine for about 2 years since then.

--Tim C.

[jleamont]

Shannon, this little tool if you have an air compressor works great and its not to expensive.

https://www.matcotools.com/catalog/product/AC91200/AIR-OPERATED-LIGHT-DUTY-VACUUM-PUMP/

Also, I would try and add Freon with one of those one shot cans you can purchase at most auto part stores. As far as searching for the leak, look closely at your compressor, when Freon leaks it often leaves an oil trail, I'd bet its either there or at your charge ports up front.

[wayne77590]

I was having basically the same problem as Shannon. Recharging, changing the evaporator, etc., did not fix the problem. I would run for about 100 miles and slowly start to creep to warm air.  I keep a thermometer in the AC vent on the dash and most of the time it would warm up to 80˚ regardless of the temperature outside. 

Finally I took it to a Freighliner place on our last trip.  They found two leaks using the dye process but the did not have the valve ports on-hand to fix it.  We ran the basement AC until we returned home and had it fixed.  It has been working every since.

I guess what I'm trying to say is that home remedies and even some professional opinions do not always work.  Best take to to the experts and get it fixed right the first time.  Cost me $285 to have the valve ports connectors replaced. That was additional to the Freightliner diagnostic charges.