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Topic: rear roof AC - where do the furnace cables go? (Read 516 times) previous topic - next topic

rear roof AC - where do the furnace cables go?

So in preparation for all my upcoming projects and especially in preparation for spending some time in cold weather again I'll have to do some upgrade on my furnace.

Here's the problem: Some coaches seem to have two furnace units, one in the rear, the other in front. My 34" model just has one furnace underneath the kitchen countertop. This furnace is being controlled by Zone1 - living room. Unfortunately the air distribution isn't perfect, so more hot air is being blown towards the rear and that results in the bedroom heating up much faster than the forward area. It's getting uncomfortably hot in the bedroom before the living room reaches the setpoint temperature. Even worse when I close the bedroom door.

I had a couple of ideas to solve this:

- add a temperature controlled flap that'd close the hot air supply going to the bedroom (bad idea - that'd result in a decrease in blower air volume and eventual overheating issues of the furnace).

- add an adjustable temperature switch in the bedroom and wire it in the control circuit of the furnace to shut down the furnace before it gets too hot in the bedroom (but the bedroom already has a temperature sensor, would be cool to keep using it)

- activate the furnace feature of the second AC and wire it to also control the furnace via zone2. That'd allow me to either switch the furnace on to regulate on zone1 temperature or turn zone1 off and turn it on for zone2. The only thing necessary would be to find the cables that come down from the second AC and are probably stuffed in some corner, just waiting to be connected... Of course the mainboard jumpers would have to be changed and the control unit reset in order to support the feature...

Does anyone have an idea where I could find those cables?
I'm pretty sure they're prewired... where does the bedroom furnace sit on your larger coaches?

Cheers,
Matt
1998 U270 3402 WTFE #5260
Cummins 8.3l - Allison MD3060
600W Solar :P

Re: rear roof AC - where do the furnace cables go?

Reply #1 –
On My 36' 1993 model (225), the furnace sits under a cabinet of drawers on the passenger side, on the forward wall directly behind the large closet.
In restless dreams I walked alone.
Narrow streets of cobblestone.


'93 U225
Build 4337
'14 CRV Toad

Re: rear roof AC - where do the furnace cables go?

Reply #2 –
Install a fan midway blowing towards the front.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: rear roof AC - where do the furnace cables go?

Reply #3 –
I have shut the bedroom vent, and door in cold weather on my 34 footer with no bad effects.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: rear roof AC - where do the furnace cables go?

Reply #4 –
Quote from: jcus –
I have shut the bedroom vent, and door in cold weather on my 34 footer with no bad effects.

The manual states that it needs a minimum area for the airflow. There're four big heating hoses (front, kitchen, bath, bedroom) and some smaller ones for the compartments. The four big ones are the minimum to have, perhaps the smaller ones are enough so it doesn't overheat...

How did you close the vent?

1998 U270 3402 WTFE #5260
Cummins 8.3l - Allison MD3060
600W Solar :P

Re: rear roof AC - where do the furnace cables go?

Reply #5 –
Quote from: Matt_frbrd –
The manual states that it needs a minimum area for the airflow. There're four big heating hoses (front, kitchen, bath, bedroom) and some smaller ones for the compartments. The four big ones are the minimum to have, perhaps the smaller ones are enough so it doesn't overheat...

How did you close the vent?


Took the vent cover off and wadded up a piece of filter material and put it in the tube, just enough air got through to keep bedroom warm enough to sleep. If you are concerned about overtemps, put an ir gun on the vent closest to the furnace and read temps before and after you close off bedroom. I did not notice much difference.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: rear roof AC - where do the furnace cables go?

Reply #6 –
Quote from: Matt_frbrd –

How did you close the vent?



On mine, there's a shutoff knob right in the center of the vent.  No real adjustment, just on/off.  Not all  defusers have this.
I can snap a pic if you want.
In restless dreams I walked alone.
Narrow streets of cobblestone.


'93 U225
Build 4337
'14 CRV Toad
 

Re: rear roof AC - where do the furnace cables go?

Reply #7 –
Quote from: Moby –

On mine, there's a shutoff knob right in the center of the vent.  No real adjustment, just on/off.  Not all  defusers have this.
I can snap a pic if you want.


Hm good idea, I found this one here: RV Discount Suppliers Furnace/AC Vent w/damper 4" black RV Camper Trailer

unfortunately it's not automated. When it's cold at night, I don't need to have the whole coach at a regulated temperature, keeping the bedroom temperature regulated and the rest of the oach somewaht heated, should be enogh.

I guess the really best idea will be to install an additional thermostat in the bedroom that'll turn the furnace on and off from there. Advantage over the over the integrationa s "zone2" will be that it's less work and the thermostat will be adjustable right from the bedroom without me having to walk to the front. In addition I'm again thinking about a motorized flap that'll close the bedroom furnace outlet ata given temperature in the bedroom. Since some of you reported that they either have a manual shutoff or have successfully blocked the bedroom outlet, I'm less worried about the furnace overheating, but will keep a close eye on the temperatures before and after modification.
I'll keep you posted!

Thanks,
Matt
1998 U270 3402 WTFE #5260
Cummins 8.3l - Allison MD3060
600W Solar :P