Appliance adapter too big for woodstove opening

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IdahoDan

New Member
Dec 6, 2018
7
Coeur d’Alene, ID
Hello! I’m am installing an older woodstove in my fireplace with a flexible chimney liner. The liner is an 8” kit. The problem I have is that the opening on top of the woodstove is about 7 1/2” and the appliance adapter that comes with the liner kit just won’t fit in the hole properly. I have looked online and found adapters that convert from 8” to 7”, but I fear that the 1/4” of space between the pipe and woodstove opening would cause a safetey issue. Does anyone know where I can find an adapter that goes from 8 to 7 1/2” inches. I am open to any suggestions. Thanks!
 
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Hello! I’m am installing an older woodstove in my fireplace with a flexible chimney liner. The liner is an 8” kit. The problem I have is that the opening on top of the woodstove is about 7 1/2” and the appliance adapter that comes with the liner kit just won’t fit in the hole properly. I have looked online and found adapters that concert from 8” to 7”, but I fear that the 1/4” of space between the pipe and woodstove opening would cause a safetey issue. Does anyone know where I can find an adapter that goes from 8 to 7 1/2” inches. I am open to any suggestions. Thanks!
It is probably an old one where the pipe slides over the collar. It isn't right but you probably don't have a choice.
 
It is probably an old one where the pipe slides over the collar. It isn't right but you probably don't have a choice.

Thanks for responding! I thought it might help to send a picture of the woodstove opening.
The outside opening is actually a little shy of 7 3/4” and the inside opening is 6 3/4”
 

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Thanks for responding! I thought it might help to send a picture of the woodstove opening.
The outside opening is actually a little shy of 7 3/4” and the inside opening is 6 3/4”
In that case you may need something custom made
 
Maybe install the 7" adapter with some 3/8" rope gasket packed around the adapter?
 
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That’s an odd size. As mentioned above, some old stoves had 8” of flue collars, the pipe went over the collar. They made what’s called a skirted adaptor for this application, but most people just ran their pipe upside down. Without a flue collar that extends up above the top it wouldn’t help though. Can you just crimp the adaptor more aggressively?
 
That’s an odd size. As mentioned above, some old stoves had 8” of flue collars, the pipe went over the collar. They made what’s called a skirted adaptor for this application, but most people just ran their pipe upside down. Without a flue collar that extends up above the top it wouldn’t help though. Can you just crimp the adaptor more aggressively?

Thanks for the info! Yeah actually tried to crimp it with this tool! But it didn’t effect it all that much.
 

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To hook up an insert an elbow is almost always needed. We don’t use adjustable elbows though, I’ve seen too many of them come apart when they are under stress.
 
I bought both 15-and 30-degree fixed elbows from Rockford. Here they are. They always take me a little while to find since they aren't where I think they should be. :)

https://www.rockfordchimneysupply.com/316ti-liner-components/round-components

The kit my chimney guy bought from National Chimney Supply had a straight adapter. I made a cardboard silhouette of the side of my insert and marked where the liner would have to be attached. I then put it in the fireplace, and thought that installation might be easier with an elbow, as mentioned above. My chimney guy used the 30-degree adapter.
 
I bought both 15-and 30-degree fixed elbows from Rockford. Here they are. They always take me a little while to find since they aren't where I think they should be. :)

https://www.rockfordchimneysupply.com/316ti-liner-components/round-components

The kit my chimney guy bought from National Chimney Supply had a straight adapter. I made a cardboard silhouette of the side of my insert and marked where the liner would have to be attached. I then put it in the fireplace, and thought that installation might be easier with an elbow, as mentioned above. My chimney guy used the 30-degree adapter.
Good work. But I’m surprised your chimney guy didn’t have elbows. We literally take every elbow and several custom adaptors to every job. We probably only do 2 or 3 a year that don’t require an elbow.
 
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He does chimney cleaning and mostly general handyman services. He pretty much stopped doing installs a while ago. He did mine since I know him. So, he doesn't keep install stuff on hand.
 
I bought both 15-and 30-degree fixed elbows from Rockford. Here they are. They always take me a little while to find since they aren't where I think they should be. :)

https://www.rockfordchimneysupply.com/316ti-liner-components/round-components

The kit my chimney guy bought from National Chimney Supply had a straight adapter. I made a cardboard silhouette of the side of my insert and marked where the liner would have to be attached. I then put it in the fireplace, and thought that installation might be easier with an elbow, as mentioned above. My chimney guy used the 30-degree adapter.

Thanks for the info