Originally Posted by bskane10
Does anyone know why we're getting black burn marks, soot-like residue on the grate covering the gas heater/pilot light box on the outside of our Airstream Bambi?? The pilot seems to be lighting fine - no problems. We've got hot water, gas works fine on the stove tops and the fridge is cold. Should I be worried about a gas line problem? - this a new one. Hasn't done this before.....
Is it your water heater or your furnace? A helpful tech adjusted our water heater by reducing the amount of air entering the burn propane feed pipe just as it feeds into the burn tube. He did it to reduce the noise but what it did was increase the carbon generated and marked the exhaust grille. I went back in and re-adjusted it, turned the flame more blue again and solved the problem. The black deposits burned off eventually.
I've added a picture of the water heater - the adjusting tube is in the green circle and the screw to release the tube is marked with the yellow arrow. - more air makes it louder and cleaner, less air makes it quieter but more dirty. You can experiment whilst it's on if you're brave!
Apologies if it's not your water heater that's causing the problem!