Insulated Chimney Liner or Not, help me determine

[Nhdigger]

The chimney is a masonry exterior setup that is 30ft tall. Its 6 years old and in good shape.

The stove is a 6 year old Woodstock Soap Stone Absolute Steel Hybrid. This is our primary heat source and has been since installing it 6 years ago.

Every year I clean the chimney 2-3 times a year and we burn about 3 cords of wood a year. Because the stove is such a modern stove its stack temps are very cool. This is causing pretty gummy creosote to build up as the chimney is exterior. I can typically get about a gallons worth of dry creosote when I clean (combined through the 2-3 cleanings) it but can still see a varnish on the tile in a few places. Woodstock says run an insulated liner while the mason says its best to run the chimney as designed and built.

I am wonder if a insulated liner would actually make a decent difference in build up as well as stove performance? Stove works great but can be a pain at times to keep converter lit off. I burn decently dry wood (1 year dried) ash, maple, elm.

I can burn an entire load and keep the cat engaged and putting off great heat however the stack temps are 200 degrees roughly.

Continue on doing it as I have been or spend the money on a liner and hope to see an improvement? I dont really mind spending the money as long as it makes a difference. Thanks for the input

 

[bholler]

The chimney is a masonry exterior setup that is 30ft tall. Its 6 years old and in good shape.

The stove is a 6 year old Woodstock Soap Stone Absolute Steel Hybrid. This is our primary heat source and has been since installing it 6 years ago.

Every year I clean the chimney 2-3 times a year and we burn about 3 cords of wood a year. Because the stove is such a modern stove its stack temps are very cool. This is causing pretty gummy creosote to build up as the chimney is exterior. I can typically get about a gallons worth of dry creosote when I clean it but can still see a varnish on the tile in a few places. Woodstock says run an insulated liner while the mason says its best to run the chimney as designed and built.

I am wonder if a insulated liner would actually make a decent difference in build up as well as stove performance? Stove works great but can be a pain at times to keep converter lit off. I burn decently dry wood (1 year dried) ash, maple, elm.

I can burn an entire load and keep the cat engaged and putting off great heat however the stack temps are 200 degrees roughly.

Continue on doing it as I have been or spend the money on a liner and hope to see an improvement? I dont really mind spending the money as long as it makes a difference. Thanks for the input

Yes an insulated liner will help but whatever you do pipe temps that low are going to cause creosote buildup. What moisture content is your wood at

 

[Nhdigger]

Average is 20%. I think its mainly just the nature of the beast having an exterior chimney running the stove lower for longer burns.

 

[bholler]

Average is 20%. I think its mainly just the nature of the beast having an exterior chimney running the stove lower for longer burns.

No. It is not the nature of the beast to get a gallon of creosote 3 times a year. Something is very wrong

 

[EbS-P]

Do you have a damper now? 30’ of insulated 6’ might need one. Can you verify your 1” clearance to combustibles for the entire chimney? Might be another reason to install 6” insulated liner.

 

[Nhdigger]

My mistake, a combined gallon through the year. Not each cleaning.

Edited my post to correct

 

[bholler]

My mistake, a combined gallon through the year. Not each cleaning.

Edited my post to correct

That still isn't good at all. But not crazy

 

[Nhdigger]

Do you have a damper now? 30’ of insulated 6’ might need one. Can you verify your 1” clearance to combustibles for the entire chimney? Might be another reason to install 6” insulated liner.

I do have just an inline damper right off the stove itself.

I am not sure I understand your question about the 1" clearance to combustibles for the entire chimney?

 

[Nhdigger]

That still isn't good at all. But not crazy

Agreed, its more than I like to see but cleaning it a few times makes me okay with it. Its the varnish I cant get off thats bothersome to me.

 

[EbS-P]

I do have just an inline damper right off the stove itself.

I am not sure I understand your question about the 1" clearance to combustibles for the entire chimney?

Code says the external chimney needs 1” clearance to combustibles. That means all framing, roof decking ect. (Interior need 2”) many/most don’t have the needed clearance or at some point someone like a roofer installed some combustibles too close.

 

[MountainStoveGuy]

what size is the flue collar on your stove? What size is the clay flue tile you are hooked up to currently?

 

[Nhdigger]

what size is the flue collar on your stove? What size is the clay flue tile you are hooked up to currently?

I would need to measure but its a standard size rectangular one, decently large.

The flue tile is 6 inch as well as the stove pipe.

As far as I know the chimney meets all code requirements, a licensed mason installed it. It absolutely does where it goes through the wall as we cut out many studs, re framed and built a large brick section in where it passes through to the exterior.

 

[bholler]

Agreed, its more than I like to see but cleaning it a few times makes me okay with it. Its the varnish I cant get off thats bothersome to me.

Yes glaze is bad especially if you don't have the required clearances

 

[bholler]

I would need to measure but its a standard size rectangular one, decently large.

The flue tile is 6 inch as well as the stove pipe.

As far as I know the chimney meets all code requirements, a licensed mason installed it. It absolutely does where it goes through the wall as we cut out many studs, re framed and built a large brick section in where it passes through to the exterior.

Was the opening 32" square? That's what's required to go through the wall.

 

[Nhdigger]

Was the opening 32" square? That's what's required to go through the wall.

Easily yes

 

[bholler]

Easily yes

Ok good. How was it dealt with on the outside of the house

 

[Nhdigger]

Its the same outside and then flashed to the siding. Chimney does stand off the house and uses metal brackets to tie into the house as it goes up.

 

[bholler]

Its the same outside and then flashed to the siding. Chimney does stand off the house and uses metal brackets to tie into the house as it goes up.

Ok in that case you should be good from a safety standpoint. But performance will absolutely be improved by a properly sized and insulated liner

 

[Nhdigger]

Ok in that case you should be good from a safety standpoint. But performance will absolutely be improved by a properly sized and insulated liner

Thank you for the input, thats what I wanted to hear. I will order up a liner and install it

 

[bholler]

Thank you for the input, thats what I wanted to hear. I will order up a liner and install it

You may very well need to remove the clay liners in order to fit an insulated 6" liner

 

[Nhdigger]

Ooo, that doesnt sound like much fun. Ill go measure and do some research as I cant remember the tile size.

 

[MountainStoveGuy]

I would need to measure but its a standard size rectangular one, decently large.

The flue tile is 6 inch as well as the stove pipe.

As far as I know the chimney meets all code requirements, a licensed mason installed it. It absolutely does where it goes through the wall as we cut out many studs, re framed and built a large brick section in where it passes through to the exterior.

its not about code, or how good of shape it is. Its more about surface area and what the stove can push. The stove is designed to push 29 square inches of chimney surface area, and your chimney is likely 100- 144 square inches. Its like putting a motorcycle engine in a hummer. Match up as close as you can as your flue collar and your problems will melt away.