Thermostat Issue?

[MJohnston]

Helpful post, thanks all!!

I have a different issue. My AC will turn off when it reaches programmed temp, but then immediately turn back on. It will continue to cycle that way for hours and make the rig cooler than desired. Any advice what is causing this continuous cycling and any recommended fixes? I have a 2018 3120RL with domestic ACs and thermostats.
Thanks!
Michael


Mod Update: Post moved to a new Thread as it asks about a different subject

[DutchmenSport]

If you have the Dometic thermostat, then try removing the cover and see what happens. The cover can cause issues sometimes. If the AC runs normal again, then carefully put the cover back on. It's tricky getting those little flat pins inserted into the right slots again on the cover, but it can be done.

Also, with the cover off, you can very gently touch those aluminum pins and the thermostat will work. It's just, you need to keep the cover handy so you can see what pin you are actually touching.

Anyway, simply pull the cover straight off. See if that makes any difference. It's a starting point that costs nothing.

Good luck.

[AZ Traveler]

Michael,

Spend a few bucks and buy the MicroAir Easy Touch thermostats. Huge improvement.

[Wisconsin Retiree]

I had the same issue until recently. Last winter in Florida I messed with the domestic Thermostat and then replaced it twice with new thermostats which had absolutely no affect on the constant AC cycling on & off. I did finally spend the money and switch to the MicroAir thermostat as others had stated it solved their issues. For the most part that has been true but I did have a time or two where it briefly cycled off & on again with my new MicroAir thermostat...?? I always, I have my ceiling fan and and additional fan running to circulate air in the trailer. I recently turned off both fans to see what would happen and was pleasantly surprised the cycling ceased...I am not sure if this makes sense?? But it seems to me the location of the thermostat and potentially the air flowing in and out of that space may mess with or cause the temperature readings to fluctuate and in turn cycling the on & off?? I just know without running my fans the temp stays steady and I have no more AC cycling on & off????

[GHallof]

Micro Air. Worth every penny

[77cruiser]

Dometic thermostat POS Micro Air awesome.

[scottz]

I agree with all the comments of Micro Air; I have them.

However, I am wondering if you are hearing the units switch from high speed to low speed. If you have your fan set to auto, the unit will run on high speed until it gets near the set point, then it will pause and switch to low speed, but you can hardly hear a difference. If it's hot, low speed does not cut it and the unit will go back to high; repeat over and over. The solution is to put your fan on high, not auto.

[RMcNeal]

I had similar problems with the original Dometic CT thermostats. One problem was as you describe, the unit would cycle on/off, on/off, regardless of temperature. The second, sometimes it would cycle off when it reached the set temp then never kick back on no matter how hot it got.
The Micro Air thermostats fixed both problems!
I was skeptical at first about spending over $500 for two thermostats, but believe me, it was the best upgrade I have ever done to our rig.

[twindman]

I don't need no stinking thermostat!!!! LOL I don't think it has ever turned off more than 2 or 3 times in 10 years. Always just full on and rig is still not too cold (except maybe once a summer).

[RMcNeal]

Originally Posted by twindman

I don't need no stinking thermostat!!!! LOL I don't think it has ever turned off more than 2 or 3 times in 10 years. Always just full on and rig is still not too cold (except maybe once a summer).

In that case, just simply wire it straight through and remove the thermostat altogether. On or off, like my grandson.

[AnArky]

Originally Posted by AZ Traveler

Michael,

Spend a few bucks and buy the MicroAir Easy Touch thermostats. Huge improvement.

I second this. Definitely was a good investment.

[pyoung47]

I believe, as a previous poster indicated, this is normal operation. Just let it do its thing.

[Randy E]

Micro air for me as well. I switched both of mine out. I can now run 1 AC unit on my tiny generator with the soft start that comes with it. It starts smooth. Does not vibrate or cycle any more. I did fill the walls around each thermostat with non expanding foam. You would be surprised how much hot air was inside the walls. The best part is being able to adjust the temp in the middle of the night using my phone. I don't even get up. Fantastic product.

[RicknTee]

This happens when the system is set to Auto. Set it to High and that should fix the issue. It did for me.