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Topic: Furnace (Read 750 times) previous topic - next topic

Furnace

On my 1990 U280: I started up the furnace which is located under the sofa/foldout bed right behind the driver's seat, and it ran fine, though something is making a huge, intolerable racket, like the fan is hitting something, or bearings.... I don't know. Which was going to be my question first. Do I have to replace this furnace or is there something I can look at fixing? Has anyone come across this before? I'm pretty sure it is original factory furnace.

However, all of a sudden the furnace just stopped so now my question is: Is there a fuse or breaker that goes to this furnace that I can check?

Thanks! Susan
Susan
Chimayo, NM
1990 U280 36'

Re: Furnace

Reply #1 –
If there was an obstruction or dry bearings for the fan, the breaker or fuse may have protected it from further damage.

Wayne at FOT (Foretravel of Texas) repaired our furnace. The fan was fine, but the flame grid had been clogged by dauber nests and would not support a flame.

The furnaces are pretty generic. A good RV "house" mechanic can probably repair the furnace or advise if you need a new one.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Furnace

Reply #2 –
Do you know where I should look for the fuse and/or breaker?
Susan
Chimayo, NM
1990 U280 36'

Re: Furnace

Reply #3 –
Susan,
I just ran into this last night on our 99' U270. We just have one Atwood Excalibur furnace that suddenly disappeared from the Dometic thermostat display. It turned out that the breaker was on the fan motor under the exterior hatch where it vents to the outside. I didn't find it until I dropped the vent cover with the grill. Under that is a second black cover which swings down to reveal the motor. The breaker in ours is mounted to the motor itself. I reset it, and all was well.
Don
Quote from: Susan –
Do you know where I should look for the fuse and/or breaker?
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Furnace

Reply #4 –
Susan, Just two hrs. ago, I finished a rebuild on the same furnace in a 93 U280. If you would call me, I can walk you through some things to check to probably determine the problem. The unit should be repairable.

Gary O 615-849-2377
Gary O
2000 U320 4210

Re: Furnace

Reply #5 –
Don,

You are so right, Dometic 4 button and 5 button thermostats require a 12 volt signal from the furnace or Aqua Hot or the word "furnace" will not appear on the display. If that is the only function not working for the thermostat I always suggest first looking for a blown fuse. Faulty button switches are the biggest problem on the 4 button thermostats.
Jim Frerichs
2002 U320 42'

Re: Furnace

Reply #6 –
Don, Thank you - I found the reset button right where you said it would be. However, mine is a Hydro Flame, Model 8535H. Maybe it is the same furnace as yours. At least the reset button was same place. Susan
Susan
Chimayo, NM
1990 U280 36'

Re: Furnace

Reply #7 –
Gary,

As I mentioned to Don above, my unit is a Hydro Flame, Model 8535. I pushed the reset button and then went inside and tried to start the unit. The fan came on, but the ignition would not light, so there was no heat. I am not fulltiming, and do not need the heat right now, but am wanting to get it fixed in preparation for future travel. The heat, ignition worked before, but not today. I live outside of Seattle and as everyone knows it is very rainy and damp here. Could that be part of the problem? I tried the ignition 3 times but no go. I stopped for 5 minutes or so each time, as well. Also, there was no noisy racket with the fan this time either. The fan worked fine, but just cold air.

There is a 2nd heater in the back, under the closet that has never worked since I've had the bus. It has a different type of control on it from the front one. I opened up the outside of it to see if it needed resetting, but that did not seem to be the case on this one.

It's pouring down rain now, and probably for next few days. So, I am keeping your phone number and will take you up on your troubleshooting offer when can be out there more easily. Okay? Susan
Susan
Chimayo, NM
1990 U280 36'

Re: Furnace

Reply #8 –
Susan, stupid question here but do you have any propane in the tank?
John H
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Furnace

Reply #9 –
John,

That's not a stupid question! But yes, I do have propane, and it was turned on, and I checked it by lighting the pilot and a burner on the kitchen range. I had trouble last summer getting my frig to light and I got a can of compressed air, sprayed it around the gas area, and voila, it lit. So, maybe I should try that on the furnace. When I put my flashlight into the long horizontal tube I saw a few dead insects laying there and thought I should vacuum them out as well.
Thanks!  Susan
Susan
Chimayo, NM
1990 U280 36'

Re: Furnace

Reply #10 –
Quote from: Susan –
Gary,

As I mentioned to Don above, my unit is a Hydro Flame, Model 8535. I pushed the reset button and then went inside and tried to start the unit. The fan came on, but the ignition would not light, so there was no heat. I am not fulltiming, and do not need the heat right now, but am wanting to get it fixed in preparation for future travel. The heat, ignition worked before, but not today. I live outside of Seattle and as everyone knows it is very rainy and damp here. Could that be part of the problem? I tried the ignition 3 times but no go. I stopped for 5 minutes or so each time, as well. Also, there was no noisy racket with the fan this time either. The fan worked fine, but just cold air.

There is a 2nd heater in the back, under the closet that has never worked since I've had the bus. It has a different type of control on it from the front one. I opened up the outside of it to see if it needed resetting, but that did not seem to be the case on this one.

It's pouring down rain now, and probably for next few days. So, I am keeping your phone number and will take you up on your troubleshooting offer when can be out there more easily. Okay? Susan

I would highly suggest that you find an Atwood certified technician. My guess is that you have a propane regulator problem since both furnaces are not working, but it could be a dozen other things. Mitch, of Infinity Interiors, had a 93, U300 that nearly burned to the ground two weeks ago. He is pretty sure it was the rear furnace that he had turned on to protect the bays from freezing. A cracked combustion chamber can cause a fire so having the units checked by a Pro is a very good idea.

i had a similar rattle in my front furnace but it was just a loose screw in the sheet metal and is now fine after simply tightening the screw. It, however never quit running. HAVE IT CHECKED.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Furnace

Reply #11 –
In order for the furnace to fire up, the sail switch must work. In order for the sail switch to operate properly the DC voltage has to be good. Make sure your batteries are fully charged. Also make sure that the propane lines are fully purged on any air.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH
 

Re: Furnace

Reply #12 –
I would guess that there is a mud dauber nest in the furnace which jambed the fan and caused the breaker to trip. You should have it checked by someone who knows that model of furnace, and suggest that you contact Gary O as he just repaired one today
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