BURNT, SOOTY SMELL UPSTAIRS

[Todd]

Lately when I reload my stove with my damper open and lots of air to bring the cat back up to light off, I get this smell upstairs (stove is in the basement). I have side by side flues and thought maybe it was coming down the upstairs fireplace flue. So I plugged it up and it still stinks. Where in the heck is the stink coming from? It's only upstairs and it only happens at refueling when the chimney is at it's hottest. After I engage the cat the stink goes away. It's not a paint smell, more of a burnt soot smell. Any ideas?

The liner was swept before the season and I have gone through 1 cord of dry seasoned wood so far this year. Tomorrow I'm going to sweep the liner and see what I find.

 

[MountainStoveGuy]

i would say its coming from the negative pressure basement.

 

[Todd]

MSG,
If that was the case, wouldn't the stink sink to the basement?

I wonder if some old creasote from the clay tiles are sitting on the liner and burning and seeping through cracks into the fireplace flue, then going down the fireplace? I did sweep the original flue before inserting the liner, I'd hate to pull the liner out, but will if I can't figure this out.

 

[elkimmeg]

Todd this is a common problem in older chimneys sharing a flue in the same chase. Old code said it was ok if the flue joints were separated by 7 or more inches
truth be told motar falls out over time and finds cracks in flues and bricks today, The code is one appliance in separate chases separated by 4" solid masonry

 

[Todd]

Well I think I found the problem. I looked closer at the upstairs fireplace and where it meets the wall are cracks all around the whole thing. Must of settled over the years. You could feel the cold air and smell the stink pouring through the cracks. A good bead of caulk and I refired the stove with the damper wide open, got her extra hot, and no more stink. Yippee!

MSG and Elk were right, negative pressure from excessive draft of a hot fire sucked outside air through cracks into the adjoining fireplace flue and into the house. Thanks guys!