Forum Discussion

08_Palomono_Cam's avatar
Nov 12, 2017

(seeking advice) Furnace Wiring Burning up!

** WE FIXED THIS ISSUE!!! I WISH THERE WERE A WAY TO THANK EVERY SINGLE PERSON WHO HELPED WITH THIS ISSUE!!! Here is the fix. The previous owner built the battery/solar system without a camper chassis ground! this means that when the camper and truck were unplugged from each other, the only return ground for the appliances that use battery was through the only wire that made a direct connection from the camper chassis to the negative of the battery, which is the furnace wire. To fix this, we connected a ground wire from the battery negative to the camper chassis...then for safe sleeping and peace of mind (backup), we connected a thick ground from the furnace negative to the battery negative too. now i have no problems at all .

08 Palomino Pop up Truck Camper.

I am a novice, and enjoy learning, which is why I am hoping to get some help! In USA Ohio. Camper was made in 2008 in michigan.

The ground wire of the LP Propane furnace keeps burning up (when the furnace is off). I've owned the camper for months and this has just started happening recently.

When it burnt up the first time, I replaced the wires and control board, and fired it up. worked great for a few days no problems.... then Last night (while not in use) i caught it in the act again. I smelled burning and went back to see the ground wire RED HOT. ground wire leading from the camper to the furnace. Immediately disconnected the battery. . Insulation burnt off, and melting everything it was touching. The wire only burns between the ground terminal and where it is connected to the camper's wiring at the nut. (see photos)

I have a Suburban NT16-SE Furnace in my truck camper. This camper sits in the bed of my truck with a thick rubber mat underneath it.

It has a solar panel that leads to a regulator and voltage meter that charges a deep cycle battery. The battery then runs to the appliances.

The previous owner removed a refrigerator but i dont think its related to my issue

Here are the attached photos. With descriptions.

https://imgur.com/a/UlyK3



Happy to provide more information!
  • Cut the ground and check voltage between the connections.
    Then start disconnecting power until the ground voltage stops to isolate the source.
  • I have to agree with Drew. The ground is carrying a lot of current. If your not able to troubleshoot yourself, then find a good electrician and pay the going rate to trace the mess. BTW, there is no way I would be inside that unit with any power on until its fixed. Just too big of a safety hazard.
  • Clearly you have a high current flowing through that wire from time to time. The source of this current is not the furnace supply wire, as it shows no signs of overheating and is the same gauge as the ground wire. I rather doubt it would be the disused fridge wires, either, though it would not be at all unwise to pull the fuse for the fridge if there's nothing else on that circuit and to inspect the wire nutted ends to make sure they can't short out against anything.

    Guessing from the amount of heat generated (to melt the insulation etc), I suspect you may somehow have the full DC return current for the camper going through this wire, or a short circuit from the battery or converter going through it. I would carefully inspect the wiring between the battery, converter, DC distribution panel, and their chassis ground connections--especially the ground connections. I have seen battery wires that look OK on the outside but have corroded internally to the point of not working, so give them more than a mere visual once-over. Somewhere I think you'll find a broken ground or a positive lead shorting out against something (perhaps part of the ductwork).

    It would not be a bad idea to put an inline fuse holder and appropriately sized fuse in this ground wire until you get the problem found and fixed.