Problem with A/C fan.

[Big-B]

Hello,

My wife and I bought a 2010 Bighorn 3055 a couple of months ago and when we had the A/C running the fan wouldn't turn on when the thermostat fan setting was set to auto. It ran fine on lo or hi setting and kept running when the A/C shut off. Anyone have any ideas?

I'm guessing something in the thermostat but don't want to start replacing parts just to find out.

Thanks

 

[cookie]

You can replace the thermostat with a digital thermostat for under $20.
It's worth a shot at repair for that price.

Peace
Dave

 

[Big-B]

You can replace the thermostat with a digital thermostat for under $20.
It's worth a shot at repair for that price.

Peace
Dave

Does it have to be a thermostat for an RV or can I use a common household one?

 

[wdk450]

Does it have to be a thermostat for an RV or can I use a common household one?

You might want to check out this old thread: https://heartlandowners.org/showthread.php/18140-Adding-an-Accurate-Thermostat-to-your-Coach?

What happens when you are on AC, and the system turns on? Just the compressor runs, or nothing at all?. The fan running on "FAN" tells you that you have good power to the rooftop AC unit, and some signals communication from the thermostat. There is a control circuit board in the inside access to the air conditioner (inside a metal enclosure box). This board takes the signals from the thermostat, and outputs power to run the fan and compressor via control relays on the board. This board also sends out 12 volt control signals to the heater system. You might want to call the air conditioner manufacturer (Dometic?) service phone number for advice ( http://www.dometic.com/USA/About-Dometic/Contact-Dometic-USA/ ).

Good luck!!

 

[Big-B]

You might want to check out this old thread: https://heartlandowners.org/showthread.php/18140-Adding-an-Accurate-Thermostat-to-your-Coach?

What happens when you are on AC, and the system turns on? Just the compressor runs, or nothing at all?. The fan running on "FAN" tells you that you have good power to the rooftop AC unit, and some signals communication from the thermostat. There is a control circuit board in the inside access to the air conditioner (inside a metal enclosure box). This board takes the signals from the thermostat, and outputs power to run the fan and compressor via control relays on the board. This board also sends out 12 volt control signals to the heater system. You might want to call the air conditioner manufacturer (Dometic?) service phone number for advice ( http://www.dometic.com/USA/About-Dometic/Contact-Dometic-USA/ ).

Good luck!!

Thanks for the information guys. I think the thread shown above will be helpful in fixing the problem.

I can't recall if the compressor is running or not when the A/C is turned on without the fan switch being in the on position. It may be worth replacing the thermostat to find out if that is the problem.

 

[cookie]

Does it have to be a thermostat for an RV or can I use a common household one?

Sorry that I did not reply sooner.
You can use any residential thermostat.
Walmart sells the Hunter brand and if you have a Menards near you, you can pick up a Honeywell and they have the 11% Rebate right now.

Peace
Dave

 

[Big-B]

I think the problem is fixed. Finally had a tech come over and look at it because the furnace wasn't working. He put a new thermostat in and the heat works fine now. Not sure about the A/C fan because it is too cold here to try it right now. Thanks for the helpful comments.