How to connect to this thimble?

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burnt03

Feeling the Heat
Oct 30, 2011
264
Peachland, BC, Canada
Another stupid question....

Took a closer look at the thimble, looks like the ID is 8" with the flue being 6x10.

img2323ym.jpg


How do I connect to this? If it's 8" stove pipe, can I just use a male x male from thimble to 90 (with 90 being female on horiz and male on vert), then female (top) x male (bottom)? How do you seal the stovepipe, just with high temp silicone or....???

If it's 6" stovepipe, can you buy 8" x 6" reducers?

Thanks for any replies!
 
Yes, you can buy reducers and increasers from 6 to 8". That might be your horiz. run. If so, the double-end crimp is correct. I prefer to seal the thimble joint with furnace cement. It's higher temp than any silicone.
 
You can also run a 6" right into the flue & pack rockwool
or unfaced fiberglass (gasp!) around the 6" & then add your
trim collar to clean it up.
 
Thanks for the quick replies!

One of my concerns with putting a stove in was that a 6" stove outlet is quite a bit smaller than the chimney x-sec. area.

But if the chimney is in good shape, I guess a stove designed with an 8" outlet would work pretty well? (50 in2 vs. 60 in2)
 
Packing some rock wool around piece of SS works really well. Put a length of SS pipe in there, up to the point where the thimble meets the clay. Center this pipe in the thimble with the insulation. If you use a sealant around the connection it will have to be re-done every year when it's cleaned, this gets messy. With the SS, it can stay in there and be brushed out. If you go with an 8" set up, then you would need to connect to the thimble that you already have. Buy a few different pieces and see what fits the best. As long as it fits tight, no sealant is necessary. Make sure you install the stove pipe with the male ends down.
 
Had a sweep in last month, told me that this is a piece of chimney that was used as a thimble. They suggested either a proper listed wall pass-through (450 + tax) or a basic SS breech pipe (295 + tax), depending on what is in the wall. I mentioned the 6" going through the existing with insulation around it, but they didn't really say much about it.

So, they've suggested removing the existing thimble first, to see what's in there. If I do need to remove it, how do I get the thing out? Angle grinder and pry bars?
 
8 to 6 reducer, double crimped.... the insulated pipe you have thru the wall is backwards, BTW.
 
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