Old Stove-wooden thimble clearance?

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costove

Member
Hearth Supporter
Oct 2, 2009
7
Colorado
Recently discovered the thimble above my "Sweet Home" wood stove is made of wood. Stove was installed over 25 yrs. ago in a condo bld. The thimble connects to a slanted cathedral ceiling & it appears to have approx. 2 1/2"- 2 3/4" air clearance around the pipe inside.

The interior wood surface inside the thimble appears to be o.k (as best as I could see with flash light & mirror)..no visible blackenimg or soot. I was told that over years, the wooden thimble could dry out and become a fire hazard.

I use the stove only on very cold days & burn around 250 lbs. of wood/winter. I installed a thermometer on the stove pipe approx 3' above the stove and monitor it closely so the fires stay <450 degrees. The stove & chimney is cleaned once a year. I really love this stove since it heats so well. I probably can't afford a major overhaul so I'm hoping to get some expert opinions on how dangerous this situation really is.

Will try to send photo attachment tomorrow.
 
Pictures will help. I strongly doubt the thimble (or ceiling support box?) has a wood chase for the chimney, especially in a condo. How did this get discovered?
 
The last chimney sweep noticed it and mentioned it to me. I climbed up on a ladder, removed the screws from the bottom metal plate and was able to peer inside even if I wasn't able to remove the plate. It's definitely wood inside.
 
Prolly a matter of terms then. Without pictures it's hard to visualize. Are you saying that the ceiling support box for the high temperature flue pipe is made out of wood? Suppose that could be possible. If so, the flue pipe used and clearances to this pipe to the nearest combustibles is worth knowing.
 
Yes, it's the support box. I measured the distance from the pipe surface to the inside surface of the "box" and it was approx. 2 1/2" to 2 3/4".
 
I would expect a condo with multiple units to be inspected by building and fire officials. If the correct class A pipe was used and the support box honors proper clearances than it could be ok. A shot of what is actually supporting the flue pipe heading out of the building would help.
 
Here's photos of the set-up. I removed the screws from the panel under the support box so it might look a bit loose. Also included shots of a crack on the box...can't tell if it goes totally through to the inside.
 

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I'm already feeling better about my attempt to install a woodstove in that shed I'm building. I'm gonna let somebody in the "know" speak to this one, but I'm thinking the following:
1. that chase is pretty darn close to that stove pipe for my liking
2. it's hard to tell from pics and I'm not familiar with your stove, but I'm thinking clearances on the back and sides may be violated
3. I'm hoping you don't have a wood subfloor, because I'm looking at your stove and thinking it probably calls for more than ember protection underneath.

Anyway, let's hear from some people that have some knowledge about your particular stove.
 
From the pictures it looks like someone made a cathedral support box out of wood to support the "hopefully" class A HT pipe. For that part it does look like there is well over 2" clearance from the class A. The single wall is not pretty, but appears to have the required 18" clearances.

That said, if it were my home, I'd be tearing it all out and updating it with a modern flue system and stove.
 
It does make me feel uneasy too. Am having someone come over and give me a quote on how much it would cost to
change the pipes and support box.

Thanks for your opinions.
 
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