both ac units suddenly shut off

[kennyredtruck]

have dual ac units and have had issue with units shutting off by themselves. Both units seem to do it. can be running both or just one unit and it still happens. thermostat is still in on position but unit is not running. shut off and turn back on and runs. then can run 20 minutes or days before it happens again. any ideas what is causing this?

Did some reading on dometic ac unit installation. Said it was very important for the placement of the foam tape. So opened both units and foam tape had come loose and was not stuck in the proper position. Re attached tape in both units. 93 degrees today both units ran all day long with no problems. Hope this solves the problem. I am going back with some aluminum tape and tape down the edges of foam tape.

 

[danemayer]

I'm guessing you mean you maybe have the thermostat set to 72 but they shut off when it's still 80?

It would be unusual to have 2 separate thermostats and 2 separate A/C units doing the same thing. So it might be logical to look for a common cause.

You do need 12V DC to operate the thermostat. If voltage falls below 12V, it could cause intermittent operation on both thermostats.

If the A/C units are both ducted, you might check the return air filters to see if they need to be cleaned. When return air flow is restricted, a typical symptom is icing up of the A/C unit, which would shut down the unit until the ice melts.

 

[Lou_and_Bette]

Are you running the AC's with the fan in the "auto" mode? If you run the units in low fan mode, they can freeze up. This freezing occurs more rapidly when the humidity is higher and may explain why they shut off at varying times.

 

[danemayer]

What coach do you have?