A/C problem

[TiredMom57]

We have a Dometic A/C that's stalling out. It stalls anywhere from 1-5 seconds then comes back on. Sometimes it comes back on blowing stronger than it did before it stalled. Anyone have this problem or can give advice to a solution? We had a tech come out and he had to change the control board b/c the wires and wire caps were burned!!

Thanks!

[TiredMom57]

So does anyone know how to do the diagnostics on the panel board?

[TiredMom57]

Thanks for all the replies. It's funny how the tech appeared to know everything about the unit but never said what y'all are saying....that this is normal. His response was always "don't know why it's doing this"!! It is a digital thermostat.

[lenr]

Thanks to the OP for motivating me to do something about this. It actually was keeping us awake in the night on the last camping trip. On a sunny day with hot weather, it's not noticeable because the AC just runs continuously.

[lenr]

Our Dometic AC does the same even at low outside temperatures at night when it only needs to run infrequently. In auto, it runs on low for a while, then the fan goes off while the compressor continues to run for 5 seconds, then the fan comes back on high for about 30 seconds, and then the whole thing shuts off for a while. There is no doubt in my mind that the temperature never gets more than a degree or two from set point. It does not make sense to me that this is the auto special feature. If Dometic can’t come up with a fix, I’ll rewire the whole darn thing to run on a residential thermostat—no this probably won’t be the simple re-wires that have been posted on this site.

[Hondavalk]

See page 8 & 11.

http://www.dometic.com/QBank/EPiServer/Dometic/US/Manuals/RV-manuals/Air-Conditioning/Single-Zone-LC...

[Learjet]

Durhamcutter wrote:
We have the same problem, it is your digital thermostat and two Tecks have told us that it was suppose to do that. I don't like it either but it how it is suppose to work, don't know why they just said that it was the digital thermostat. Good Luck and happy camping

I guess that is why the call it a "special feature", the problem seems to be when the temperature is right at the change over point between hi and lo, they should have done something different with the software in the T-stat to prevent this.

The work-around is don't use AUTO until the temperature is reached in the RV and has stabilized. My New RV in my sig. has done this since day one. I have 2 units with separate T-Stats and they each do this.

[Durhamcutter]

We have the same problem, it is your digital thermostat and two Tecks have told us that it was suppose to do that. I don't like it either but it how it is suppose to work, don't know why they just said that it was the digital thermostat. Good Luck and happy camping

[tvman44]

Might also be a bad fan motor. Those bushings are famous for seizing up.

[Larryect]

I don't think so.......

[Learjet]

Larryect wrote:
Mine operates as Learjet described. Shuts down the fan for a few seconds when changing fan speed when fan is in auto.

Ok...so is there a bunch of defective control boards for the Dometic AC's ?

[Larryect]

Mine operates as Learjet described. Shuts down the fan for a few seconds when changing fan speed when fan is in auto.

[GASMAN6674]

Mine was doing this, would be running then fan would stop for 6-10 seconds while compressor was still running. It was a bad board in the unit according to the dealer. He replaced it under warranty and no more issues.
Hope this helps

[Learjet]

TiredMom57 wrote:
We have a Dometic A/C that's stalling out. It stalls anywhere from 1-5 seconds then comes back on. Sometimes it comes back on blowing stronger than it did before it stalled. Anyone have this problem or can give advice to a solution? We had a tech come out and he had to change the control board b/c the wires and wire caps were burned!!

Thanks!

Are you running the fan in Auto?

I have the Single Zone LCD Thermostat, when the Fan is in AUTO as it approaches the correct temp, the fan will shut off for a few seconds to switches to low then start back up, the compressor keeps running during this swap over. Sometimes it does this again to high. I run the Fan in Hi or Low until the temp is stabil in the unit, then Auto works fine.

here is the info from the manual on the "special feature"

Special Features
Auto Fan
When auto fan is selected the fan speed will vary depending on the
difference between the temperature set-point and the room temperature.
In auto fan the compressor and fan cycle On and Off with the
thermostat.
When the difference is:
>5º The fan operates on HIGH
<4º The fan operates on LOW

[TiredMom57]

OK, thanks for your time!