Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Susan on January 28, 2013, 01:51:58 pm
Title: Furnace
Post by: Susan on January 28, 2013, 01:51:58 pm
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
Title: Re: Furnace
Post by: J. D. Stevens on January 28, 2013, 02:02:20 pm
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.
Title: Re: Furnace
Post by: Susan on January 28, 2013, 02:14:41 pm
Do you know where I should look for the fuse and/or breaker?
Title: Re: Furnace
Post by: Don & Tys on January 28, 2013, 03:14:13 pm
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
Do you know where I should look for the fuse and/or breaker?
Title: Re: Furnace
Post by: Gary Omel (RIP) on January 28, 2013, 03:41:34 pm
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
Title: Re: Furnace
Post by: Jim Frerichs on January 28, 2013, 03:56:28 pm
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.
Title: Re: Furnace
Post by: Susan on January 28, 2013, 06:09:37 pm
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
Title: Re: Furnace
Post by: Susan on January 28, 2013, 06:23:56 pm
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
Title: Re: Furnace
Post by: John Haygarth on January 28, 2013, 06:32:48 pm
Susan, stupid question here but do you have any propane in the tank? John H
Title: Re: Furnace
Post by: Susan on January 28, 2013, 07:02:05 pm
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
Title: Re: Furnace
Post by: Kent Speers on January 28, 2013, 07:04:06 pm
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.
Title: Re: Furnace
Post by: Peter & Beth on January 28, 2013, 07:37:19 pm
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.
Title: Re: Furnace
Post by: red tractor on January 28, 2013, 09:28:56 pm
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