Someone cut my thimble? Now what?

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mrkbeck

New Member
Nov 28, 2023
3
New Hampshire
So I bought a house which has an exterior masonry (cinder block) chimney. On the inside there appears to be a thimble running through sheetrock, but when I pulled the cover off this is what I found and I'm not sure what I'm looking at.

It appears to be a short length of 6" pipe on the inside with a couple screws holding it to a T inside the chimney, and 8 inch pipe on the outside. Idk if it's some sort of thimble that got cut or someone's attempt to make their own double wall pipe.

Now what do I do? Do I need to cut a gigantic hole in my wall to rip this thing out? What would i need to replace it with? Can I make this work somehow?

From what I understand I need double wall stovepipe connected to this thing because the vertical run of pipe will be less than 18" from the wall.

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I'm not an installer, so hopefully BeGreen will see your post. It looks like a wall thimble to attach your stove pipe to, but I believe they are always stainless steel, which I don't think this is. I'll be curious to hear the answer. If that inner part is shiny stainless steel, I think you just need double wall pipe to attach to it.

The 18" will just depend on your stove clearances. With double wall and heat shield, you might be okay with that distance.
 
Thank you for the reply. Minimum stove clearance is 8 inches according to the manual. The stove sits at 8.5" right now due to the small floor pad in order to give me the 16" I need in front.

The inner pipe I think is just black stove pipe. It's metallic color on the inside but has some surface rust and is noticably more dull than the T it connects to in the chimney, which is definitely stainless.

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Thank you for the reply. Minimum stove clearance is 8 inches according to the manual. The stove sits at 8.5" right now due to the small floor pad in order to give me the 16" I need in front.

The inner pipe I think is just black stove pipe. It's metallic color on the inside but has some surface rust and is noticably more dull than the T it connects to in the chimney, which is definitely stainless.

View attachment 319742 View attachment 319743
I can't really tell what that is but it certainly doesn't look right have you had it inspected by a pro?
 
The one I installed had a wall thickness super donut out of insulation material of some kind. It butted up against the chimney on 1 end and went all the way through the wall to the face plate.

You'll want to get somebody in to look at that.
 
Problem is I booked an appointment but they can't make it until January 22. So I guess I get to stare at it until then 😂.
Yeah it's that time of year. If they weren't booked atleast a month out I would be concerned
 
Looks like a janky splice on the tee snout, but that's just a guess from the photos. Black stove pipe can not pass into a wall.

It does lead to concern that other corners were cut, most notably clearances around the thimble. It may take some wall surgery to find this out.
 
You can always tear it all out and put it together right. It’s not rocket science.

Buy the thimble kit to find out what’s required, cut the drywall and add the framing if it’s needed. Hopefully you don’t need to fix any drywall. If so, that’s not bad, install the thimble.
 
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