Ovaling of chimney liner and connection to round adapter

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CharlieTuna

New Member
Jan 10, 2021
52
PA
So, the 7.5 inch chimney liner ovals from passing through the damper. I have an adapter to fit that to a 6 inch outlet on the top of the stove. How much will the band clamp on the top of the adapter pull in and round the ovaled chimney liner? I haven't tightened it up yet as the installation isn't quite complete. Is there something I can or should do to try to round the ovaling more? It looks like it will need a bit of sealant.
 
No sealant unless you want a stinky chimney. May I ask why a 7.5" liner if its going to be connected to a stove requiring a 6" outlet?
 
No sealant unless you want a stinky chimney. May I ask why a 7.5" liner if its going to be connected to a stove requiring a 6" outlet?

The 7.5" liner is preexisting from the old stove. I didn't see a need to replace, and certainly not in the middle of the winter.

Using stove gasket cement where the chimney liner fits into the adapter will make it stink? I was going to use that where the bottom of the adapter meets stove too.
 
The 7.5" liner is preexisting from the old stove. I didn't see a need to replace, and certainly not in the middle of the winter.

Using stove gasket cement where the chimney liner fits into the adapter will make it stink? I was going to use that where the bottom of the adapter meets stove too.
No sealant should be needed for liner connections they should fit right enough on their own if you are using the proper components and installing them correctly.

Btw I doubt your liner is a 7.5" liner. It is much more likely a 7". A 7.5" would have been a custom order size no one makes it.
 
No sealant should be needed for liner connections they should fit right enough on their own if you are using the proper components and installing them correctly.

Btw I doubt your liner is a 7.5" liner. It is much more likely a 7". A 7.5" would have been a custom order size no one makes it.

Well, it is definitely a 7.5 inch liner. I needed a custom built adapter made for it. I can give a plug for Dan's Rugged Pipe in Lisbon Falls, Maine. I had to make a cut into that for the damper control. It's quite close to the top of the stove. So, I used gasket sealant around the adapter and the stove for good measure. I also had nuts welded to it for where it connects to the brackets on the stove top. My concern was the ovalling of the liner fitting the round adapter, but everything is connected and working properly. I wrapped some gasket rope around where the liner fits in to the adapter for good measure.
 
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Well, it is definitely a 7.5 inch liner. I needed a custom built adapter made for it. I can give a plug for Dan's Rugged Pipe in Lisbon Maine. I had to make a cut into that for the damper control. It's quite close to the top of the stove. So, I used gasket sealant around the adapter and the stove for good measure. I also had nuts welded to it for where it connects to the brackets on the stove top. My concern was the ovalling of the liner fitting the round adapter, but everything is connected and working properly. I wrapped some gasket rope around where the liner fits in to the adapter for good measure.
Sounds good gasket sealant won't smell it will probably crack and fall out but won't hurt anything. The 7.5" thing just doesn't make sense to me. I have been doing this a long time and never heard of or seen any pipe fittings or stoves in 7.5. that is an odd one
 
Sounds good gasket sealant won't smell it will probably crack and fall out but won't hurt anything. The 7.5" thing just doesn't make sense to me. I have been doing this a long time and never heard of or seen any pipe fittings or stoves in 7.5. that is an odd one

Occasionally, there are downdraft issues under certain weather conditions when starting a fire. I figured the gasket sealant should help with that, or other issues with drafts in the house from an open door, or whatever. The old stove had a 7" port on the top, but the liner that was installed was 7.5", with an adapter to match. I don't know if that was normal, but it all works now. Maybe someone got a deal on 7.5" liner.
 
Occasionally, there are downdraft issues under certain weather conditions when starting a fire. I figured the gasket sealant should help with that, or other issues with drafts in the house from an open door, or whatever. The old stove had a 7" port on the top, but the liner that was installed was 7.5", with an adapter to match. I don't know if that was normal, but it all works now. Maybe someone got a deal on 7.5" liner.
The ww large had an 8" oval outlet small has 6". Insulation on the liner would help with the cold startups by allowing the liner to get up to temp much faster.
 
The ww large had an 8" oval outlet small has 6". Insulation on the liner would help with the cold startups by allowing the liner to get up to temp much faster.

The ww large had an 8" oval outlet small has 6". Insulation on the liner would help with the cold startups by allowing the liner to get up to temp much faster.

That came with an oval exhaust port (flue collar) that connected to a VC "flex connector" system that went through the damper. When the chimney liner was installed, an adapter was bolted on to the top of the stove with a round port. I still have the old adapter fitting around somewhere. It was 7" at the bottom and expanded at the top to fit the 7.5" liner.
 
That came with an oval exhaust port (flue collar) that connected to a VC "flex connector" system that went through the damper. When the chimney liner was installed, an adapter was bolted on to the top of the stove with a round port. I still have the old adapter fitting around somewhere. It was 7" at the bottom and expanded at the top to fit the 7.5" liner.
Why did they bolt an adapter to the stove it makes no sense. Why not just ovalize an 8" adapter and put it in the stove outlet.

I know you didn't do it so I am not being critical of you at all just saying it makes no sense to do it that way.

Is the liner 7.5" inside or outside? Heavy wall or light wall? You got it hooked up now so it doesn't matter much. I am just curious that's all
 
Why did they bolt an adapter to the stove it makes no sense. Why not just ovalize an 8" adapter and put it in the stove outlet.

I know you didn't do it so I am not being critical of you at all just saying it makes no sense to do it that way.

Is the liner 7.5" inside or outside? Heavy wall or light wall? You got it hooked up now so it doesn't matter much. I am just curious that's all

I cut off about an inch from the liner with tin shears because I wanted the stove up a little higher. I measure the metal at .3 mm thick, which is .012 inch thick. From my notes, I think it was 7.5" outer diameter. I wasn't too worried about that because the adapter had a band at the top that adjusted. I could take a measurement when the stove cools down in the morning.

My guess is that they wanted to use the 7.5" liner for whatever reason, or they wanted to pad the bill by adding the adapter... At this point I have no complaints. I am very happy with the present stove.

I still have the old stove in the garage. The top plate of it cracked. I am toying with the idea of converting it to a secondary system if I get bored. It has tremendous mass.
 
I cut off about an inch from the liner with tin shears because I wanted the stove up a little higher. I measure the metal at .3 mm thick, which is .012 inch thick. From my notes, I think it was 7.5" outer diameter. I wasn't too worried about that because the adapter had a band at the top that adjusted. I could take a measurement when the stove cools down in the morning.

My guess is that they wanted to use the 7.5" liner for whatever reason, or they wanted to pad the bill by adding the adapter... At this point I have no complaints. I am very happy with the present stove.
What type of construction was the liner? The one on the right or the left?
 

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Ok that is light wall they are much larger od than id it is probably a 7" liner

Could be. From my notes, the circumference was 23.5", which works out to 7.48" diameter. I couldn't measure the inside as easily as it had ovaled. It all works now. When the season ends, I'll look at the top. It isn't that old, and the WW didn't burn so hot. From the websites I found, higher temps could shorten the life of stainless steel:
 
Could be. From my notes, the circumference was 23.5", which works out to 7.48" diameter. I couldn't measure the inside as easily as it had ovaled. It all works now. When the season ends, I'll look at the top. It isn't that old, and the WW didn't burn so hot. From the websites I found, higher temps could shorten the life of stainless steel:
WWs barely burned so yeah no problem with overheating there lol. I know it worked out I was just curious what was going on.
 
WWs barely burned so yeah no problem with overheating there lol. I know it worked out I was just curious what was going on.

It just amazes me how many businesses don't have complete measurements online for their products. Do-it-yourselfers don't always know which measurement they need to know. A product might also be used to improvise something else, but without the measurements being advertised, the company loses sales. In this case, Dan in Maine got the business.
 
It just amazes me how many businesses don't have complete measurements online for their products. Do-it-yourselfers don't always know which measurement they need to know. A product might also be used to improvise something else, but without the measurements being advertised, the company loses sales. In this case, Dan in Maine got the business.
They don't give those measurements because they don't want to encourage mixing types or brands of liners and components. It voids the ul listing if you do. As long as it is the right type of fitting and fits well there shouldn't be any safety issue. But it would open them up to liability
 
They don't give those measurements because they don't want to encourage mixing types or brands of liners and components. It voids the ul listing if you do. As long as it is the right type of fitting and fits well there shouldn't be any safety issue. But it would open them up to liability

Maybe. It's an over litigious society in many ways, but Dan in Maine had no problems making it custom. I've had the same problem getting measurements for PVC pipe for use with gardening. It may just be a certain laziness in marketing. Failing to accurately list products online results in lost sales, as well as returns.