Loose chimney connection

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BlazeKingSaddles

New Member
Nov 18, 2018
18
Northeast
Wondering if someone has an opinion on this:

i’ve got a 12 foot length of double wall chimney that is loose at the top where it inserts into the class a double wall pipe. My best guess is that it was knocked loose after the chimney was swept.

This is the second time it’s happened.

The first time, the installer wrapped a gasket around the pipe and then tightened the collar which connects the two pipes. I gave them a call and asked if it was still safe to operate until it can be fixed, to which they replied yes.

They said there is no chance that the chimney could collapse and I’m aware that any airgap would not emit spoke, but something still doesn’t seem right operating the stove with a loose chimney.

Any thoughts or suggestions would be greatly appreciated!
 
By double-wall chimney, do you mean the connecting stove pipe to the class A chimney? Normally a properly installed stove pipe mechanically connects to the class A chimney. Can you post a picture or two of this connection that is loose?

Moved to a new thread as this is a different topic.
 
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By double-wall chimney, do you mean the connecting stove pipe to the class A chimney? Normally a properly installed stove pipe mechanically connects to the class A chimney. Can you post a picture or two of this connection that is loose?
Moved to a new thread as this is a different topic.
Yes, that’s correct. You can see the collar inbetween the stove pipe in the Sellkirk class a. When they did the install, there definitely was no mechanical connection between the two pieces.
[Hearth.com] Loose chimney connection
 

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I can’t tell what’s going on there exactly. Every pipe joint requires 3 screws at each joint. The top and the stovetop can be grey areas that manufacturers don’t really address. At the top, we pre-drill and use 1” SS screws to secure the connector pipe to the chimney adaptor. You shouldn’t use screws long enough to penetrate the inner wall of double wall pipe typically, but with Selkirk in particular, there’s no other way to fasten it securely.
 
I can’t tell what’s going on there exactly. Every pipe joint requires 3 screws at each joint. The top and the stovetop can be grey areas that manufacturers don’t really address. At the top, we pre-drill and use 1” SS screws to secure the connector pipe to the chimney adaptor. You shouldn’t use screws long enough to penetrate the inner wall of double wall pipe typically, but with Selkirk in particular, there’s no other way to fasten it securely.
Think it’s safe to operate? and do you think that the gap would let in too much ambient air that would cool the chimney?
 
It looks like they used that trim piece that comes with the connector pipe, the gap just appears to be around it. Behind it the pipe should cover about 2.5” of crimped stovepipe adaptor. Assuming they used all the factory pieces, it should be fine like it is. I’d still get some screws in it at some point, especially if there are any elbows in the pipe.
 
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The first time, the installer wrapped a gasket around the pipe and then tightened the collar which connects the two pipes
This collar only covers up the unfinished male end of the upper pipe, it does not replace any fasteners or fasten anything.
 
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This collar only covers up the unfinished male end of the upper pipe, it does not replace any fasteners or fasten anything.
No functional purpose in supporting the chimney then, I suppose. The first time they came to fix it, they wrapped a piece of loading door gasket behind the collar before tightening it back up. l suppose to fill in the gap to stop the pipe from rattling around. Trying to remember if the bottom of the Selkirk pipe has a lip that they could fire 3 screws into.
Thank You for the suggestions and apologies for posting in the wrong thread. Still learning how to navigate this forum.
 
[Hearth.com] Loose chimney connection
I found this picture of the class A Selkirk pipe before the connector pipe was installed. If what Webby3650 is saying—that the top can be grey areas the manufacturers don’t really address—it’s any wonder how a successful connection between the connector pipe and the class a pipe can be made. Especially since the collar/trim piece doesn’t fasten the two and there’s apparently no place on the class A pipe to screw into the connector pipe.
 
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That’s why we shoot 3 screws through the double wall pipe and through the stovepipe adaptor. It’s rock solid then. We’ve got other ways to make a secure connection at the stovetop. We don’t just set an adaptor on there and hope for the best..
 
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I found this picture of the class A Selkirk pipe before the connector pipe was installed. If what Webby3650 is saying—that the top can be grey areas the manufacturers don’t really address—it’s any wonder how a successful connection between the connector pipe and the class a pipe can be made. Especially since the collar/trim piece doesn’t fasten the two and there’s apparently no place on the class A pipe to screw into the connector pipe.
Looks like you may not have 2” of clearance there. Why did they use a roof support rather than a cathedral ceiling support box?
 
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Looks like you may not have 2” of clearance there. Why did they use a roof support rather than a cathedral ceiling support box?

I had them cut more of the drywall to be 2” away before installing the ceiling cover. I elected not to do the CCS for aesthetic purposes (wife said “no way”)

I contacted Sellkirk and apparently, this is the solution to my problem:
[Hearth.com] Loose chimney connection
 
I had them cut more of the drywall to be 2” away before installing the ceiling cover. I elected not to do the CCS for aesthetic purposes (wife said “no way”)

I contacted Sellkirk and apparently, this is the solution to my problem:
View attachment 242039
There’s nothing new about that piece, not sure why they call it new?
That won’t help anything. Your current pipe adaptor is already 4” long or so. It shouldn’t fall off, but securing it would keep it from being sloppy. Why not just have the installers properly secure it? How did they attach it at the stovetop?
 
There’s nothing new about that piece, not sure why they call it new?
That won’t help anything. Your current pipe adaptor is already 4” long or so. It shouldn’t fall off, but securing it would keep it from being sloppy. Why not just have the installers properly secure it? How did they attach it at the stovetop?

I’m hoping that it will be properly secured by using the above-pictured adapter. It would twist and lock from underneath into the Sure-Temp and then slide inside of the connector pipe under it and then be screwed in securely. One of the connectors in my existing chimney is telescoping, so I would think it would adjust properly.

On the stovetop, the connector is overlapping the flue collar.
 
I’m hoping that it will be properly secured by using the above-pictured adapter. It would twist and lock from underneath into the Sure-Temp and then slide inside of the connector pipe under it and then be screwed in securely. One of the connectors in my existing chimney is telescoping, so I would think it would adjust properly.

On the stovetop, the connector is overlapping the flue collar.
So it’s just sitting there on the flue collar not secured in anyway like most then..

What I’m trying to say is that you have an adaptor just like the one pictured already in place, only shorter. It’s under that “beauty band”. There’s no reason to buy another part unless your installer didn’t put an adaptor in there at all. ? The only benefit of that DSAC is if you didn’t have a slip in the stove pipe. It acts as a slip in single wall pipe applications.