Did I catch my rig about to burn ?

No. That's just incomplete combustion from not getting enough air into the burner. Blockage or maladjustment. Since the air valve is clamped down well, I'd look first for blockage.

Maybe I should not say this. But, put four or five inch pieces of dog flea & tick collar into all three heaters. Just lay them on the floor of the enclosure. I found this solution on this site in maybe 2008. After I had a web stop my water heater while camping at Denali. Have not had the problem since on a TT, then a Class A and now on the Chateau.

When I take a flea collar off the dog and I remember (close to dirt). I just cut it up and add to what is already there.

I only run my hot water heater until it shuts down then turn off and start again when needed. Usually means it is run twice a day. Dick

PUCampin wrote:

tpi wrote:
Usually when that happens there's a spider web in burner (mixer) tube. Happened to me before.

Same here, and it takes VERY LITTLE in that tube to mess up the mixture because the gas pressure is so low into the burner tube. In my case, when I removed the burner tube I looked inside, saw nothing, blew in it and reinstalled. Same issue. After no luck solving the problem I removed the burner tube a looked with a flash light and could just barely make out so wisps of cobwebs. I blew in it but they stayed. I used a stick to clean them out, reinstalled and problem solved. So cobwebs that were barely visible that did not seem to impede gas flow at all were enough to mess up the mixture and make the burner run improperly.

Exactly what happened with mine. Easy fix but deadly if you don't.

tpi wrote:
Usually when that happens there's a spider web in burner (mixer) tube. Happened to me before.

Me too.

tpi wrote:
Usually when that happens there's a spider web in burner (mixer) tube. Happened to me before.

Same here, and it takes VERY LITTLE in that tube to mess up the mixture because the gas pressure is so low into the burner tube. In my case, when I removed the burner tube I looked inside, saw nothing, blew in it and reinstalled. Same issue. After no luck solving the problem I removed the burner tube a looked with a flash light and could just barely make out so wisps of cobwebs. I blew in it but they stayed. I used a stick to clean them out, reinstalled and problem solved. So cobwebs that were barely visible that did not seem to impede gas flow at all were enough to mess up the mixture and make the burner run improperly.

Funny but the heater has been on for the past two weeks constantly, I wonder if a spider decided last night to get in there, we do have quite a few here. I use compressed air to clean my rig before and after trips especially the fridge vent. Im inside it right now going nose to tail. Come to think of it I turned the heater off yesterday when I arrived home.

Funny story, been hearing a knock inside, sounded like a tapping on the window, re arranged the cabinets ,etc during my travels, even narrowed it down by rocking the rig while parked . Planned on having the DW ride with me to narrow it down( she doesn't like drag racing as much as I do so I hit the road for 2 weeks by myself, Sonoma/Seattle events) anyway I get home and look up and I believe the pull strap from the awning is the culprit, it's sticking out more than normal, well being solo I could enjoy my classic rock a little louder....to drown out the tapping you see....

First thing is be sure it's clean. Compressed air. I blow out the furnace and frig too a couple times a year.

Usually when that happens there's a spider web in burner (mixer) tube. Happened to me before.

I had a similar thing happen to my water heater. Turned out there was a mud dauber nest in tube that mixes LP and air. Cleaned it out and cleaned up soot from side of MH and water heater cover. I now have a SS screen cover over the vent. Spiders can also create the problem.