A/C Gremlin

[sandcar361]

Okay need some thoughts on my latest new coach gremlin. Running all 3 a\c units at home plugged in or sitting out running on the genny they work awesome. We have traveled from Phoenix to San Diego 2 times in the past 2 weeks and both times all 3 a\c units stop making cold air while driving. I wonder if the wind turbulence on the roof is effecting their performance? I know it should not but something is going on while driving. Got pretty warm yesterday on the drive home. Maybe units are freezing up but all three?

[PDFOR3]

Are you running the generator while driving? I think you should for A/C operation in the coach.

[sandcar361]

Sorry not sure why my signature is not working. My coach is a 2021 Berkshire XLT 45A

[sandcar361]

Yes genny running while driving

[Maingler]

If i had to guess ambient temps on that trip were 100+ and the roof is in excess of 110 115 degrees. You werent able to cycle enough of the interior air with the exterior to eventually cool down the unit. You're correct Air turbelance combined with those ambient temps will effect any of these air system efficiency.

[D W]

Originally Posted by Maingler

If i had to guess ambient temps on that trip were 100+ and the roof is in excess of 110 115 degrees. You werent able to cycle enough of the interior air with the exterior to eventually cool down the unit. You're correct Air turbelance combined with those ambient temps will effect any of these air system efficiency.

X2. If you don't have the correct directional airflow your A/C can not condense, nor can it evaporate, and the cooling will stop.

[Trappfarmer]

Next time that happens make a pit stop and tell us whet happens while stopped.

[sandcar361]

I think you guys are all on the right track. Temps both trips above 108 and I think the turbulence is not letting them get the proper airflow. Yes once I stop they work perfectly but by then its 100 inside and miserable. My coach also has one of the winguard dish set ups on top and that has to create some bad wind up top also. Living in Phoenix this is going to be a problem I need to get resolved. I wonder if I ran with the cover removed if it would make a difference? Sure would look ugly though lol.

[tradventures]

I would keep the fans on high for two reasons
1. You get full coldness (not sure if that is a word) off the evaporator when compressor shuts off plus better circulation basically more efficient in high heat.
2. If the issue is compressors going off on high pressure due to not proper air flow over condenser the internal circulation blower fan might help a little with all that.

[Trappfarmer]

If your ACs are Coleman Mach give them a call at
574-247-9235.
They have a great tech group.
Those units are very Aerodynamic. Turbulence really should not be a problem.
We know it doesn’t work at cruise. We know it does work at full stop. We don’t know about in between. That Cummins doesn’t mind pushing our XL 40E at the maximum cruise control limit of 75. Maybe we just slow down a little? Nope, that’s why we have air horns. Good luck! I have a call out to Coleman for another issue but will raise the issue while I have them on the phone and post if they offer a solution.
Obey all traffic laws and posted speed limits. Wink,wink.

[sandcar361]

Update:
Reached out to Coleman and never got a call back so I reached out to Forest River today to see what they say (no response as of this post)
As suggested I lowered my speed to 60 miles an hour and still lost all three units. This has now happened 4 out of the last 6 trips and always during the heat of the day over 95 deg outside. I truly think they are not getting the proper airflow and are overheating. Stay tuned!!

[Lincman983]

Do the roof top a/c units cool down the coach while stopped or when the coach is parked? It's pointing to an air velocity issue. What is happening is the condenser coils aren't radiating or dissipating the heat efficiently due to the turbulence of the air and then coupled with high roof temps just makes them work harder in my opinion

[sandcar361]

They do work again once you stop but you have to turn them off then back on again to reset them. They will not just start cooling on their own when you come to a stop. Almost like they have to be hard reset to work again. I looked at them closer last night and you could run the back half of the cover off and it looks like it would get more airflow. I am leaving on another trip from Phoenix to Sacramento this coming Thursday and it is going to be warm for sure if I cant get this figured out.