Horrible, Awful, Stinky, etc......FURNANCE HEATER SMELL!!!

[Fosters]

My 1st 5th Wheel (or RV for that manner) so an LP furnace new to me. We all know that in a regular house dwelling that has Natural Gas and one has a leak, it smells like "bad eggs" right? Well, the smell in my coach is not bad eggs when I put the heat on, so it is not a leak. Assuming Natural Gas leak smells the same as LP Gas? Nevertheless, I well believe it is NOT a LP leak I have.

It is something else. Without you obviously able to smell it, I can try to describe it as certainly something burning and emitting a very nausea odor. A burning smelly odor. No smoke comes from the vents. And it is strongest once she turns on, but never subsides. Kinda lingers. My first winter and been running the heat for like 2 weeks now. And nothing is changing, ain't better ain't worse. And I don't have the funds to have a Pro RV Tech come inspect the system.

I have read some postings elsewhere about mice droppings in the duct work or worse, mice nests!!! Now, I have no idea what a burning mouse smells like. But would love to put one on fire and see if that is my culprit!!! I can buy the fact of a burning mouse causing the odor. But not those very, very little black poop mouse droppings. Unless there is a s**t load of them in my duct work?

Surely, someone has experienced the same at some point? Mice smell or something totally different?

Thanks so much to all of you in advance!

[SCClockDr]

Check the outside cover fit. I had a burning plastic type small last year and found 3 of the screws loose. This allowed exhaust blowback which started to melt stuff in the burner area. Replaced the short OEM screws with longer ones, issue solved.

[WILDEBILL308]

Most likely it is just the dust and dirt burning off the first time you have used it in a season. Same problem in regular hous. I make shure I fire up the furnace for the first time when the DW is out. The last time when she was home she wanted to call the fire department because something was burning.
Bill

[wrgrs50s]

Normally the return air vent is right in front of the furnace. You can unscrew the cover, then unscrew the furnace access panel, and look into the furnace to see if there is anything in there.

As others have stated if it's new it will smell a burning smell for a while. A mouse could have made a nest inside and the paper or nesting material could be the burning smell. You can even disconnect one of the ducts where it connects to the furnace and just shine a flashlight in for a quick view.

Also, I had a friend that had a wasp nest in the exhaust pipe that somehow backed a smell into the trailer. Might be worth checking if all else looks ok.

[SDcampowneroper]

Propane and Natural Gas ( methane) have no natural odor. An odor is added called mercaptan, a sulfur compound similar to skunk scent from which it was originally refined.
If your odor is not skunky, and its not the new construction burning off lube and paint smell, then? Tell us what it smells like.
Best idea is run it a long time, even cover some vents to raise the furnace and duct temp to burn up the stuff. Dont worry, it wont overheat, the furnace has a high temp limit that will not let it harm you.

[doxiemom11]

We had a mouse in our furnace once. It didn't smell as it got pretty crispy fast when that burner came on. We bought used, so didn't have odor from a new furnace, so don't know what that smells like. Hopefully it will go away soon for you.

[Johno02]

Maybe a dead critter??

[BFL13]

No mice here! When the LP furnace comes on first it smells out of the vents like burning LP, but that smell goes away quickly.

So you must be right, there is something else. Did you take the floor vent covers off and use a vacuum cleaner? The vent trunking under the trailer is hard to get at if you have an underbelly. Rusty screws and can't see that close under the trailer with the bifocals--no fun at all! 😞

[DutchmenSport]

You did not say if your camper is brand new or not. And you did not say if you have ever run the furnace before now.

If this is the very first time the furnace is run ... yes!!!! You will have same awful smells. It happens to every camper the first time the furnace is lit up. What is happening is the heat is burning off the oils in the furnace, the oils on the heat ducts. Yes, it smells awful. It may even burn your eyes and make it impossible to breathe.

You need to let the furnace run for a good half hour, non-stop (on high), maybe even longer. Open all your windows so it can air out. After it burns the first time, shut the furnace down. Keep those windows open to air it out. Once aired out, you can fire up the furnace again and the smells and burning, irritation in the eyes will no longer be there.

And ... don't be surprised if your smoke alarm and AND your CO2 detector fires off also. (Our did on our first 2 travel trailers.) Our third camper (our current one), the dealer ran the furnace and burned off the oils before we took delivery. I asked them specifically to do this. Third time, I learned!

Now ... if you have previously run your furnace, then I have no clue what the problem may be.