Community Forums

Chuck&Pam · 10-30-2017, 07:16 PM

Anyone know where the fuse is that supplies 12v to the heat/ac thermostat? My heat quit over the weekend and now the AC will not function either. I'm thinking one of the first things to do is to be sure the tstat is still working. The fuse panel under the bed doesn't have it and the panel under the dash is only automotive type functions. Isn't there a fuse box under the front hood where it may be located? Or am I looking in the wrong place?

I'll try to call fleetwood tomorrow during my lunch break but wanted to get a head start with this forum if possible.

Thanks!

j.smith · 10-30-2017, 09:45 PM

In the panel under the bed, fuse #3, marked appliances. Pretty sure that is the one that supplies power to the thermostat and heater on my coach.

j.smith · 10-30-2017, 09:50 PM

Just looked at the 12v electrical drawings, circuit #3 should be the correct one

Chuck&Pam · 10-31-2017, 04:10 AM

Thanks...I'll get out there in a few minutes and check it.

Chuck&Pam · 10-31-2017, 07:35 AM

Well...that's not the problem then because all the 12v fuses under the bed are good. I'll give Fleetwood a call later.

Any other ideas?

Chuck&Pam · 10-31-2017, 10:08 AM

...and of course, they are closed during lunch time.

j.smith · 10-31-2017, 11:38 AM

I had a problem once where the circuit board for the furnace was getting wet during heavy rains causing the fan to run continuously at a slow speed. I puled the cover and besides correcting the water thing, found a switch that I thought would secure the power to the furnace but found out that when it was shut off neither the furnace or the air conditioner would work. I assumed that it was somehow interrupting the power to the thermostat, probably miswired at the factory but I corrected the water issue and never got back to chasing down the switch functionality. I know it's a long shot, but if someone has had the cover off your furnace it might be worth looking at.

If you PM me an email address I will send you the power and plumbing drawings for the coach. I have a 2016 29T but I think the drawings are applicable to the 26 and 29 series coaches.

Chuck&Pam · 10-31-2017, 11:54 AM

Yep..that's what happened to me...very heavy rain a couple weeks ago and the fan wouldn't stop. I took the furnace cover off and there's a off\reset switch I turned off to kill the furnace fan. I reset it and now nothing works.

Chuck&Pam · 10-31-2017, 11:59 AM

Maybe I just don't know how the reset works??? I don't have any doc on the furnace.

j.smith · 10-31-2017, 01:49 PM

Ok, here's what I got on that switch. It is just on/off, no reset position. The power to the thermostat is tied to the closed side of the switch so if the switch is failed or the downstream side of the switch is shorted the thermostat will not get any power.

The problem I had with mine was that the control board was sitting in water, causing it to short. Once it was removed and cleaned up it starting working again. I ultimately replaced it with a board from Dinosaur as the Dino board is conformal coated and has standoffs to keep it up out of the water. Check to make sure your board is not sitting in water, it does not take much to cause it not to function. I have the manual for the furnace and a diagram for the furnace wiring but cannot upload the image. PM me with an email address and I will send them to you.

Chuck&Pam · 10-31-2017, 02:07 PM

PM sent.
The board was sitting in water but it is completely dry now. I'll not need the heat next week but possibly the a/c. Wonder if I could jump past that switch to get power to the tstat so a/c will work?

Chuck&Pam · 11-01-2017, 07:05 PM

yea! it was that "off/reset" switch. Not sure if it just got wet and corroded a bit, or if it is bad. I finally had some time to spend on it this afternoon and Thanks to Jeff...i was able to trace the tstat power to that switch on the furnace. I cleaned it a bit and reset the wires on the terminals and it started working. It may stop working again as we bump down the road, but at least I know I can jiggle it a bit and get it to connect.

I'm definitely going to look at the Dinosaur board as a replacement.

Jeff.. was there any other work you did to keep the water from getting in there?

j.smith · 11-01-2017, 07:28 PM

I don't think so, just cleaned up the seal (if I remember correctly it is an o-ring), put a little lube on it and tightened evenly all around. Been a couple of heavy downpours since and no further problems.

Chuck&Pam · 11-01-2017, 08:09 PM

OK.. maybe thats the problem, I don't see any seals or o-rings on mine. Maybe it was just installed wrong. There's no seal of any kind on the exhaust vent which is where the water seems to be getting in. I'll go back and check that install manual and use some silicone sealant on it when I get back.