Should the Air Conditioner Fan Cycle Off?

My fan runs as long as the AC is turned on. The compressor cycles off and on. I've had other ACs, too, and they did likewise.

bobbolotune wrote:
I have a Coleman 9 Low Profile Ceiling Control air conditioner. Always when the air conditioner is turned on the fan runs constantly. The compressor cycles on and off, but the fan never turns off. It has been this way since the air conditioner was brand new.

I asked someone in a campground if his air conditioning fan does this and he said no. He said that with his air conditioner the fan cycles off after the compressor cycles off, the same as a home air conditioner.

So now I am wondering if my air conditioner might be broken. That the fan should cycle off. Otherwise this must be different for different air conditioners. He was in a big Class A and my air conditioner is for a truck camper. Maybe the design is different.

The manual gives no hints about this question. I think this is a common air conditioner. So for others who have the same air conditioner, does your fan run constantly or does the fan cycle off?

I have been concerned especially if running the air conditioner all night that the fan could burn out from constantly running for 8 or more hours straight.

I have the same AC unit & mine operates just like yours..... I was wondering the same thing. :)

On the thermostat, if the fan is set to "Auto" it will run only when the compressor runs. If the fan is set to "Run" the fan will run continuously and the compressor will cycle.

My toy hauler had a fan delay after the compressor cut off. My TC fan runs all the time like others have posted. I think it is due to the cheap thermostat rather than the AC unit.

AC mod
This is how I got mine to shut off plus a digital thermostat is lots more accurate

If it has the controls up on the AC, yes the compressor cycles on and off but fan continues to run. by running the fan all the time it causes air to be drawn over temp bulb so it knows when to cycle the compressor on and off.

but here in SE PA, I found compressor runs, temps and humidify goes down. Compressor shuts off, but coil is wet so fan starts to evaporate moisture off coil and sent it back into coach, humidify starts to rise. I was seeing humidify swing from low 40's to upper 90% between compressor on and off.


I installed a digital Heat/cool thermostat on wall. wired Heat to run Heat, than ran 2 wires from Cool terminals down to a compartment in fuse box I put a 120V 30A relay (with 12V coil). The thermostat turns this relay on and off. The relay opens/closes AC power that goes up to AC unit.

I now control the fan speed on AC shroud, turn AC shroud thermostat to lowest setting, and use wall thermostat to control AC set temps. Now fan and compressor both shut off. Works great. Even starts with my Honda 2000 in eco mode.

note, I only use my Honda to run the AC, when on generator I run hot water/refer on propane, and I turn the breaker off for camper charger. I than switch my outlets over to Inverter so Sat system don't reboot every time AC starts.

Towpro,what size/ make AC unit do you have?
Thanks,Mike

I have a Coleman Mach (I?), an oldie but a goodie on my TC. Fan runs constantly while the compressor cycles. There is no "Auto" setting for the fan, just "Lo", another "Lo", and "Hi".

Don't worry about the fan running for 8 hours. You're not going to wear it out or burn it up under normal circumstances, as it was designed to run for thousands of hours. If it does burn up it wasn't any good in the first place.

Our TC came with a t-stat that includes 'auto' or 'on' for the fan. This Coleman model is what we have and it works great:

https://www.amazon.com/Coleman-Digital-Heat-Thermostat-8330-3362/dp/B004RCOU9Y

popeyemth wrote:
Towpro,what size/ make AC unit do you have?
Thanks,Mike

coleman mach 8 9200.
Here is the thermostate I use.

Here is the relay I used. It has 12Vdc coil and its rated Contact Voltage AC Nom: 250 V Contact current Max: 30A. (don't forget to solder the solid AC wire into spade connectors that attach to relay. Just crimp might not be enough.)

I have been keeping my eyes open for a timer relay that I can use so I can delay either the compressor or fan startup a couple seconds, but its probably not even needed.