Community Forums

ROAquaman · 06-26-2016, 11:27 AM

Hello all,

I have a dash AC problem maybe someone has some insight on.
My rig is a 2002 Chevy 8.1 Vortec.
The dash AC puts out cold air just fine as long as I'm driving down the highway, but as soon as I come to a stop and sit idle for a short time, air will get hot. Fan works fine just the temperature of air is the issue.

Any ideas?

Thanks and happy travels!

Oemtech · 06-26-2016, 01:53 PM

Quote:

Originally Posted by ROAquaman

Hello all,

I have a dash AC problem maybe someone has some insight on.
My rig is a 2002 Chevy 8.1 Vortec.
The dash AC puts out cold air just fine as long as I'm driving down the highway, but as soon as I come to a stop and sit idle for a short time, air will get hot. Fan works fine just the temperature of air is the issue.

Any ideas?

Thanks and happy travels!

Open the hood and look where the fresh air intake is on the AC/heater box.... In town and idle your sucking engine heat. Switch to recirculation mode and your problem will go away.

jdarends · 07-04-2016, 12:37 PM

My atco tempcon valve wasn't closing all the way allowing heater core flow. Installed inline ball valve n AC works much better

George Z · 07-04-2016, 01:52 PM

Also installed a ball valve and use the Max air setting which re-cools interior air instead of outside air

TweetThisRV · 07-04-2016, 08:28 PM

I have a 2011 Southwind and wonder what the air temp should be coming out of the vent? Seems mine runs warmer than it should on AC and AC recerc mode.

K5RJS · 07-12-2016, 07:38 PM

Quote:

Originally Posted by ROAquaman

Hello all,

I have a dash AC problem maybe someone has some insight on.
My rig is a 2002 Chevy 8.1 Vortec.
The dash AC puts out cold air just fine as long as I'm driving down the highway, but as soon as I come to a stop and sit idle for a short time, air will get hot. Fan works fine just the temperature of air is the issue.

Any ideas?

Thanks and happy travels!

My 2005 HR with the 8.1 engines had an old style R-12 condenser (tube & fin) sandwiched between the transmission cooler & radiator. This condenser is not very effective with R-134A. Modern refrigerant (134A) works best with a parallel flow condenser. With the transmission cooler in front of the old style condenser the air temperature was already warm before entering the a/c condenser and resulted in poor performance of the dash a/c. I checked the input and output tubes on the condenser and found it only dropped the temperature 10 degrees thus not allowing the gas to return to a complete liquid state. This is a design issue and will never produce the best results.
I replaced the factory condenser with a modern parallel flow model of similar size and relocated the transmission cooler below the condenser. My a/c works much better now and the radiator receives more and cooler air for the engine cooling. The oil cooler also works better as more air moves through the core with the reduced back pressure. If you use the max air which recirculates inside air there will be a very slight difference between moving and stopped performance, only the reduced rpm will effect the cooling. It was a pain doing the mod since the line fittings are not standard but I can explain the modification to anyone interested.
Hope this helps.....

Starsekr · 07-19-2016, 01:43 AM

Are you in Max AC or just AC? I think Max AC applies max vacuum to a flap that controls air flow over cooling/heater core, keeping cool. AC will vary vacuum, allowing heat/cool mix. If you have a vacuum leak, this will also happen. These are colored tubes green, blue, black, coming out of dash into engine area. There is also a vacuum reservoir in the front under the front window. Do a visual for cracked tubes.

TweetThisRV · 07-20-2016, 10:10 PM

I would like to know more about that mod - sounds like it might be similar to my "issue."

max49 · 07-20-2016, 10:25 PM

Hi guys, I have not posted in years, just came on to see why Driver has'nt answered my PM and saw this.
My das h air works good to OK, but if I'm not moving it blows hot air, always has since the rig was new in 1995, I know thats not great but has always been that way. When I get moving it cools off again, but as always, not real fast.

angelman · 07-21-2016, 06:49 AM

Just went thru this with my brothers 03 intruder. You should have the Acme 4102930 dash climate controller. Check that you have vacuum at the controller via the black hose. If you do then select max a/c and check for vacuum under the hood via the blue vacuum hose going to the fresh air intake on the passenger side above and forward of the battery. If no vacuum then you have a bad controller. If vacuum is present check the diaphragm with a vacuum tester. His turned out to be a bad controller. We tapped into the black vacuum line with a "T" and fed the blue vacuum line permanently to keep the diaphragm in max a/c mode. The module is $125.00 used on the internet. Good luck.

BTW on his trip back to florida he said the a/c worked fantastically. Where before if he slowed down for any reason the dash air would blow warm at best.

TweetThisRV · 07-21-2016, 06:08 PM

Quote:

Originally Posted by Starsekr

Are you in Max AC or just AC? I think Max AC applies max vacuum to a flap that controls air flow over cooling/heater core, keeping cool. AC will vary vacuum, allowing heat/cool mix. If you have a vacuum leak, this will also happen. These are colored tubes green, blue, black, coming out of dash into engine area. There is also a vacuum reservoir in the front under the front window. Do a visual for cracked tubes.

No cracked tube(s) that I can see - when I have it on Max (recerc AC mode) the air blows at out about 58 degrees on the road - outside temp 93 degrees. Is that the best I can hope for?

Could it be as simple as a vacuum issue or maybe a recharge and balance of the system?

George Z · 07-22-2016, 04:34 AM

A 40 degree difference would be about the most you could expect so the 35 degrees you are seeing is not bad at all.Much of the problem is the volume of air in the MH you are trying to cool.

Starsekr · 07-23-2016, 04:08 PM

If anyone is having Dash Air problems with a Tempcon system, try this website for tubing, installation and parts info: Evans Tempcon, Inc - Technical Support

If you keep a file of info on your computer, suggest you look this over and download it, never know when it won't be available anymore.

K5RJS · 07-26-2016, 11:33 PM

Quote:

Originally Posted by TweetThisRV

I would like to know more about that mod - sounds like it might be similar to my "issue."

As I described above the transmission cooler was moved and the old condenser replaced. The dryer had a unique connector and I made a new hose. The hose from the compressor also had a metric thread so I modified the existing fitting to mate with the new condenser. It's not a job for someone with little a/c experience as the system is changed quite a bit. The results were worth the effort because the a/c now blows cold instead of cool. If you want photos contact me and I'll be happy to help.