Skip to main content ↑ ↓
Topic: Back furnace not working  (Read 373 times) previous topic - next topic

Back furnace not working

Last time we used our motorhome, all the furnaces and everything works perfect. Getting ready to take off for Mobile Alabama from South Dakota ,and it's cold. Turn down the back furnace and the fan ran for a little bit and shut down ,now nothing works. I really can't find the breaker or fuse for it so I'm at a loss. thanks for anybody's help. Randy.
Linda & Randy Kemink
1996 ForeTravel U295 CAI
Build #4845
MC #17912
2017 Chevy Silverado High Country

Re: Back furnace not working

Reply #1 –
Remove the outside cover and check for 12 volts. There is a breaker in there. I think there is also a fuse at the foot of the bed. If not there check also behind the white panel in the basement.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Back furnace not working

Reply #2 –
the Atwood shop manual has a good trouble shooting section.  Find your furnace model, see the relevant electrical diagrams, run the trouble shooting steps.
If you decide you need a new printed circuit board, we recommend the Dinosaur brand over factory offering.

https://myrvworks.com/wp-content/uploads/2019/04/Atwood-Shop-Manual-HydroFlame.pdf

Ignitor Board Index page

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Back furnace not working

Reply #3 –
Thank you very much. I'll try that tomorrow.
Linda & Randy Kemink
1996 ForeTravel U295 CAI
Build #4845
MC #17912
2017 Chevy Silverado High Country

Re: Back furnace not working

Reply #4 –
Quote from: LRK –
Thank you very much. I'll try that tomorrow.
On our 1992 U225 the rear furnace is on the passenger side behind a chest of drawers with an air intake grill at floor level.  If yours is similar you can remove that grill and turn the blower wheel by hand to see if it's mechanically free or not.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Back furnace not working

Reply #5 –
I carry a spare dinosaur replacement board, sail switch, limit switch, and just replaced the blower motors. Of all the appliances I have had the most trouble with over the years it is these furnaces. I have been left without heat because of all the above parts at one point or another. Easy to diagnose, most are an easy to fix. Like Chuck and Jeanie said, look up the troubleshooting steps. It is very step 1,2,3 with these for firing order of operation.