Front A/C won't stay on

[sheena154]

We have a 2006 Monaco Diplomat. Last April we got a new Brisk front roof A/C. It worked fine for a couple of months but then started to have what my husband calls a ''Sometimer Issue".  It comes on but won't stay at the set temperature. Sometimes we have to set the control clear down to 50f before it starts and it may stay at 72-76 but it's not consistent.  He has opened the breaker panel and the hard start box and checked all the wiring but can't find anything wrong. The back A/C works fine.  Can someone help?

Patricia Neuzil

'06 Diplomat

[vito.a]

It needs to be checked by a qualified Dometic repair technician.  You probably should file a warranty claim as soon as possible.   

[trailmug]

I've had this issue before on a temperature sensor that was mounted on a slide-out. Monaco used solid thermostat wire which broke and became intermittent when bent back and forth a bunch of times. Diagnosed by putting an ohm meter on the sensor wires at the roof and moving the slide.

[Steven P]

I was gonna suggest making sure the air is not blowing directly on the sensor which is on the wall by my passenger seat in my 06 Diplomat.  Maybe even cover it up and see if it runs longer.   I agree w above,  if still under warranty, get them to check it.  Also, just resetting the thermostat could help.  

[rpasetto]

If your two ACs are controlled by separate thermostats, swapping them would tell you whether it's a thermostat problem. 

If they're on the same thermostat one of the AC's would have a remote temp sensor which might have gone bad.  Try Steven P's test first if the AC which is affected is on that sensor.   Sensors run about 20 - 30 bucks, IIRC, so a temporary plug in of a new sensor in a different location may be a good test.  Snaking the wirint would be tricky if you had to replace the sensor though.

[sheena154]

My husband stuck the phone up there and took a few pictures and saw that one of the wires had gotten crimped so he re-wired it and now it works great.  It was replaced last year and apparently the installer was a little careless.  I want to thank everyone for the suggestions.

[Scotty Hutto]

Thanks for the follow-up.  Always nice to see how the story ends.  😁