Dometic Air Conditioner problem

[Camper Sue]

Hi, I am new to this forum and a first time poster so please bare with me. Recently purchased a 2013 Wildwood 26TBSS second hand. It has a Dometic air conditioner with digital thermostat and for some reason will not stay running.Need help. It will run for 18 seconds then shut off. It does this over and over.No instruction manual came with it and can't seem to contact the previous owner. can anyone tell me whats wrong ? Or are we just not programming it properly ??

[Camper Sue]

I now have a manual but it was no help.

[DaveSchwartz]

Sounds like the compressor motor is failing to start and its overload protection is kicking in. Since its quite new, I wouldn't suspect a failure so the first thing I could think of would be a power issue.

Assuming you have a 30 amp input at the camper, what type of socket are you plugged in to and how (i.e. what kind of adapters/cords between the camper and receptacle)?

Almost no AC will start over a 30-to-15 amp adapter to a normal household circuit particularly if non-RV extension cord is in the loop.

Can you measure the voltage at an outlet with both the AC disabled and with it trying to start? Could be that the voltage is sagging too much due to insufficient conductors in the cord for the current draw.

[Camper Sue]

thanks for the reply. at the moment its plugged into our house. When we were in a 30 amp camp site last week in blistering heat that's when we noticed it would not stay on. We had the camper on 2 different camp sites , both 30 amp, same results no air conditioner.I have no way in measuring the voltage sorry.

[Herk7769]

Originally Posted by Camper Sue

thanks for the reply. at the moment its plugged into our house. When we were in a 30 amp camp site last week in blistering heat that's when we noticed it would not stay on.Failing to start . Does that mean it needs to be replaced ???

Again, without some idea of the voltage during start up it is impossible to say. Even at a campground, voltage sags in hot weather are notorious and if your compressor is already compromised, the low voltage may not be sufficient to kick it over.

The compressor rotor could also be locked. If so, you might need a replacement (might be cheaper just to buy a new one if not in warranty).

Call Dometic and see if the unit is still covered.

If not, before you buy a new one, you can try removing the fan control wire from the rear of the thermostat and see if the compressor only will run. Once the compressor rotor unlocks, it should work normally (one would hope).

Good luck...