Roof A/C running all the time

[Bill Staley]

Our 05 Patriot Thunder has 3 roof A/C units.  The front unit is set on 78, the outside temp is in the high 80s, and the unit is running constantly.  I am use to a basement A/C on out previous coach which cycled even when it was in the 90s.  Is it normal for the roof unit to run constantly with these temps?

[David T. Richelderfer]

If the room temperature doesn't get down to the thermostat setting, then why would the a/c shut off?  Just a thought... perhaps the a/c is getting weak and is not cooling efficiently/properly.

[Steve Huber]

Bill,
You've got a lot more windows in the front part of the coach so it will take more cooling time to reach the t'stat set point. Make sure the fan on all the units is set on High.  If you set the t'stat higher the unit should shut off. If not, could be bad t'stat. Next time you are near a hardware store (HD, Lowes, Harbor Freight, etc.) consider getting an IR temp probe. You can measure/compare the temp of the air coming out of the ACs.
Steve

[Bryan Beamon]

Bill with our coach if you set your tstat on auto it will shut off once it reaches temp. I was not sure in reading your comments if you were using the auto function, because the AC fan will continue to blow in low or high mode once it reaches temp.

[Bill Staley]

Thanks for all the replies.  Setting it to auto did the trick.