Potential Problem with Double Wall to Single wall connection

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mlwinchell

Member
Hearth Supporter
Mar 8, 2009
23
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I had a contractor install a true north tn20 stove into a masonry fireplace inset hearth with chase - all new stove pipe single and double wall. Where the double wall connects to the single wall and goes into chase there is this questionable connection where a crimped end of the single wall pipe is attached to the double wall adapter that goes thru masonry vertically into chase.. This guy keeps telling me it's the right way. I have not seen any other installs with exposed crimp ends used. I want to know is it just a cosmetic issue or is it a safety issue as well or am I the problem? I can get more photos if necessary.

[Hearth.com] Potential Problem with Double Wall to Single wall connection
[Hearth.com] Potential Problem with Double Wall to Single wall connection
 
I think that's a connector piece to class A? (given the difference in diameter), not just to double wall stove pipe (as indeed should not be used above that masonry).

On the other hand, the top piece goes inside the single wall, so no creosote leakage issues.

No screws visible though (should be there).
 
Yes i believe its a connector piece the pipe inside the chase is different looking. There is a 3 screws at attachment point. At minimum i feel its an aesthetic issue. Ive never seen exposed crimp on stove pipe. This isnt a shack either. I attached a few more photos to give a better idea
 

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Aesthetically I can see what you are saying.
You'd have to look at the brand list of parts (product line) to see if this is a finagled connection or not.

I do not think (if all is okay beyond what we can see here) that it's a safety issue. Pipe is properly screwed in, parts acting as male/female seems to be in the right orientation.

If the connection does not leak (i.e. if the male end from the top goes in deep enough, and is tapered a bit, to close against the smooth part of the single wall), then I think it's okay.

I believe there are wide black band clamps you could buy to cover up unsightly connections.
 
That's the part I was mentioning yes, but this is for double wall stove pipe, so it'll be more like 7".
If you have single wall stove pipe, you need a smaller version of the same.
 
I am concerned about clearances here. Normally single-wall is not used in an alcove. Was this alcove built from scratch? It doesn't look like a masonry fireplace install.

What is behind the stone veneer inside of this alcove and above the stove?
 
the alcove arch shape was made with a layer of metal screen for a gravel screening plant and i attached standard lathe to it. the metal screen is secured to wood framing with lags with fender washers. this was my first attempt at any masonry veneer arch. i would do a little longer radius next time. it is also narrower in back of the alcove to help radiate heat out. the vertical walls are 5/8 ply with lathe. the mantel (covered in cardboard in pic) is a 400# slab of colorado red sandstone i set on a 4x4 angle iron. i also drilled and epoxied 4 x 5/8 all-threads through a triple 2x8 beam and the 4x4 angle iron. i hand picked all the gray mix of local stones off sides of local roads and ditches within 20 miles of house. about 200 hours of my life complete the entire project. the drystack look is time consuming. There is lots of wood framing behind the stone in alcove and entire chase. Should I be asking the contractor to run double wall down to the stove?
 
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the alcove arch shape was made with a layer of metal screen for a gravel screening plant and i attached standard lathe to it. the metal screen is secured to wood framing with lags with fender washers. this was my first attempt at any masonry veneer arch. i would do a little longer radius next time. it is also narrower in back of the alcove to help radiate heat out. the vertical walls are 5/8 ply with lathe. the mantel (covered in cardboard in pic) is a 400# slab of colorado red sandstone i set on a 4x4 angle iron. i also drilled and epoxied 4 x 5/8 all-threads through a triple 2x8 beam and the 4x4 angle iron. i hand picked all the gray mix of local stones off sides of local roads and ditches within 20 miles of house. about 200 hours of my life complete the entire project. the drystack look is time consuming. There is lots of wood framing behind the stone in alcove and entire chase. Should I be asking the contractor to run double wall down to the stove?
Awesome job looks sweet.