Run ac fan and furnace

[vtdanokim]

I put a deposit down on a new to me 2013 Jayco White Hawk 29SQB and I'll be picking it up in a few weeks.

I was going through the camper doing an initial quick PDI and noticed the AC fan wouldn't cut on with the furnace running. Is that a normal thing? The AC fan will turn on fine if I turn the heat off. Is this something I can change? My wife loves the camper with the exception of a lack of heater vent in the front bedroom, and was hoping the fan would help circulate the heat better.

[ddrueckh]

I believe it is normal. The AC fan will only work when the selection is turned to cool, not heat.

[vtdanokim]

Originally Posted by ddrueckh

I believe it is normal. The AC fan will only work when the selection is turned to cool, not heat.

Hmm that's a bummer. Does anyone know if there's a way to modify things, maybe the thermostat, to have them both run at the same time?

[Grumpy]

You would have to install a seperate switch, but that may mess up the thermostat. I would call Coleman and talk to their tech service dept.

[vtdanokim]

I'm willing to swap out the thermostats if that'll help as well.

[troutslayer]

It will be interesting to see if you can get that done. I think the reason may be that the AC (and AC fan) are on 110 electrical and the furnace (and furnace fan) are on 12V DC. "and never the twain shall meet". Please post your outcome, cuz I'm also interested in this possibility.

[vtdanokim]

Originally Posted by troutslayer

It will be interesting to see if you can get that done. I think the reason may be that the AC (and AC fan) are on 110 electrical and the furnace (and furnace fan) are on 12V DC. "and never the twain shall meet". Please post your outcome, cuz I'm also interested in this possibility.

True, but I'm curious why when the thermostat is set to Heat, it locks out the fan from running. There's got to be a way to override this as when we were looking at new Prime Time Tracer units with the same thermostat, the salesman said we could run both to get heat into the queen bedroom.

Also, I REALLY want the ac fan to constantly run for white noise...

[Grumpy]

The 12 volt is only control voltage. It closes a relay up in the ac that turns on the fan and/ or compressor. It may be possible to add a switch, but Coleman would be who to ask.

[ninjahbob]

It may be a safety issue with the heat side, fire hazard?

[vtdanokim]

Originally Posted by Grumpy

The 12 volt is only control voltage. It closes a relay up in the ac that turns on the fan and/ or compressor. It may be possible to add a switch, but Coleman would be who to ask.

Perfect, that's the info I was looking for. Now to dig through the Coleman manual to see how I can bypass the relay.

[Grumpy]

I think you would be better off using the 12 volt control wiring. Possibly add a single pole double throw switch in the fan circuit. That way you wouldn't back feed the thermostat and it would be a lot easier.

[vtdanokim]

Originally Posted by Grumpy

I think you would be better off using the 12 volt control wiring. Possibly add a single pole double throw switch in the fan circuit. That way you wouldn't back feed the thermostat and it would be a lot easier.

Could you explain that in English? I don't speak electrical...

[norty1]

The heat comes thru the floor registers, AC comes from ceiling registers. I never heard of anyone changing that.

[vtdanokim]

Originally Posted by norty1

The heat comes thru the floor registers, AC comes from ceiling registers. I never heard of anyone changing that.

but if i can get the fan above running, it should help distribute the heat through the ceiling vents too. at least that's the theory.

[spoon059]

You have one thermostat, it is designed to control the heat OR the a/c, but not both at the same time.






If you wanted to, you could buy a second thermostat and wire the heat on one thermostat and the a/c on the other. That way you could run the a/c fan while the heat is on... but it won't really help distribute heat.

[vtdanokim]

Originally Posted by spoon059

You have one thermostat, it is designed to control the heat OR the a/c, but not both at the same time.






If you wanted to, you could buy a second thermostat and wire the heat on one thermostat and the a/c on the other. That way you could run the a/c fan while the heat is on... but it won't really help distribute heat.

It appears the Dometic brand does run both the ac's fan and the furnace at the same time. I'm primarily interested in running the fan for white noise. Any additional heat distribution is icing.

Adding an additional thermostat is definitely an interesting option.

[Paintinfool3]

I got a box fan for the bedroom and just turn it on at night for the white noise

[vtdanokim]

Originally Posted by Paintinfool3

I got a box fan for the bedroom and just turn it on at night for the white noise

But with the curtains (soon to be doors) shut, a box fan wouldn't help her with the heat issue. Hmm, I wonder if swapping the coleman mach analog thermostat with the digital one will solve the problem. Looks like some other people are able to run both at the same time with the digital thermostat.

[nylyon]

I can think of several ways this could be accomplished. As mentioned, 2 thermostats one for heat one for A/C. You could change the A/C controls to the type that are unit mounted, this would eliminate the thermostat for the A/C altogether providing completely independent control of the A/C. You could also potentially install a separate switch to force the A/C fan on, but the concern about backfeeding the electronic thermostat is possible, so it would need to be done carefully. And / or install a second A/C which ties into the existing duct work which works with an independent thermostat.

In my opinion, the 2 thermostat idea would be the best for your case. In my 5th, I have 2 A/C's and can run the front A/C in fan mode with the furnace on because it has a separate thermostat. Of course it will only take the air from the bedroom and circulate it throughout the camper.

If the goal is white noise, perhaps a free app for a tablet hooked up to a speaker would be a better option.

[troutslayer]

Originally Posted by vtdanokim

Hmm, I wonder if swapping the coleman mach analog thermostat with the digital one will solve the problem. Looks like some other people are able to run both at the same time with the digital thermostat.

I did that and it didn't change the fan "situation".