weird yellow stuff leaking down chimney

February 8, 2007 5:42 PM

Nasty yellowish liquid dripping down the brick furnace chimney into my basement....why?

It's been very cold here in Ohio, seldom getting above 15, and it's been under 10 for days, and around zero at night. I'm in an 1940s era house with a brick chimney that vents the exhaust from my furnace. Lately I noticed this nasty yellow liquid dripping down the chimney, all around it pretty much, and it's not a lot. Maybe a few ounces make it to the floor of the basement, and look really yellow. The liquid coming down the chimney is almost gummy, it's like sap almost, and in a few spots some has dried into a gummy trail just like sap along the exposed outside of the chimney in the basement. This has never happened before (i've been in here since November and it's never been this cold). I can't get in my attic yet as I've got to get an extension latter to get up there. So, I'm wondering what could be causing this. Is it condensation forming in the chimney, and coming through from the inside, or forming on the outside and dripping down? The heater has been on a lot more lately, of course, and there is some snow on the roof. Could it be melting snow somehow coming through the flashing and down the chimney? Mind you, it would have to melt from the warmth of the chimney since it hasn't been above freezing since this started. Also, prior to this deep freeze it rained like hell for weeks and I had no leaks. Any ideas anyone?

posted by Salvatorparadise to home & garden (7 comments total)

Could it be condensed sulfur-related exhaust from your forced air furnace?
posted by jeanmari at 6:47 PM on February 8, 2007

Does it taste like honey? You may have had some bees in or around your chimney this summer.
posted by kuujjuarapik at 8:24 PM on February 8, 2007

I too am curious that it might be bees. My parents had a nest of carpenter bees in their attic, and after a hot summer noticed a disgusting brownish yellow ooze dripping down the walls under the attic. (They're in the process of stripping wallpaper now that the nest is gone - it was so sticky they couldn't remove it or paint over it.) I don't think carpenter bees are honey bees per se, but there was something dripping out of the nest.
posted by librarianamy at 5:27 AM on February 9, 2007

Carpenter bees don't make honey but they do produce "castings" and debris from tunneling through wood. But there isn't any wood inside of the chimney, correct?
posted by jeanmari at 8:32 AM on February 9, 2007

Is it creosote? If so, you need to get your chimney cleaned out stat, before you have a chimney fire.
posted by Gamblor at 10:17 AM on February 9, 2007

Creosote shouldn't be coming from a gas or oil furnace. What kind of furnace are you running?
posted by kuujjuarapik at 11:18 AM on February 9, 2007

Sorry for the late comment, but it could also be fire retardent foam insulation that was misapplied. Some of the insulants have been known to melt if in contact with a constant heat source.
posted by pezdacanuck at 12:30 PM on February 13, 2007