On Sun, 02 Dec 2007 13:28:07 -0600, Duff wrote:


I have black soot coming out my ducts too. In fact, the vents in my
white ceiling and wall have to be cleaned periodically to remove the
black soot.

But there has been no fire anywhere near me. Ducts tend to pick up
soot and redistribute it in a concentrated area because they move so
much volume of air.

In addition to what you have on all the items in your home, when you
open your doors, you are letting in a tremendous amount of 'soot' that
is run thru your duct system. Also molds and all the million of
bacteria and germs you see on tv commercial.


Sound like the burner flame is not combusting completely. A red or
yellow flame indicates free carbon formed. Make a note if the furnace
walls next to the burners are sooty. Sit by the furnace when it comes
on and take a good look until it shuts off. Its fairly easy to adjust
the air/gas mixure yourself until you get a hot blue flame. Remember
the bunsen burner in high school lab?

I am winging it here. The burner combustion gases should go straight
up the flue and never get into the heated air circulation. Else you
would get carbon monoxide poisoning. Do make your own observations as
to whether you feel nauseous or "not that good" when the furnace come
on. Don't let your imagination get the better of you. But its a
precaution worth taking.