Need some advice on SS flue liner

[Wisneaky]

That's why I went with CLD the first time, their warranty allows for some DIY, only one I could find like that.
When I lined my second flue I didn't worry about it, just found a good deal on what I needed and went for it. I realized I could have bought 2 regular liners for what I spent on my first one "special HD 2 ply liner" BAH! Just a heads up for anybody wondering, the inner layer of 2 ply liner doesn't lay back down flat after it is coiled up for shipping!
I would have went with CLD on the second one but I felt they tried to pull a fast one on me concerning the shipping cost. That sent me shopping and I found a much better deal elsewhere. But that company was since bought out so...

definitely worth shopping around.

 

[fixit1960]

Just wondering, if the liner is inside a masonry flue/chimney why not just use single wall stainless steel? I had 33 ft of this inside a interior brick chimney in an old two story farm house and it ran perfect for 16 years. A lot less expensive and easier to install than double wall. Just a question, perfectly fine to use what ever you want but if price becomes and issue?

 

[Wisneaky]

Just wondering, if the liner is inside a masonry flue/chimney why not just use single wall stainless steel? I had 33 ft of this inside a interior brick chimney in an old two story farm house and it ran perfect for 16 years. A lot less expensive and easier to install than double wall. Just a question, perfectly fine to use what ever you want but if price becomes and issue?

I don't see why you couldn't. And that would be the cheapest temporary fix. Run it right down the clay liner.

 

[fixit1960]

I don't see why you couldn't. And that would be the cheapest temporary fix. Run it right down the clay liner.

Unless he wants to redo the chimney because of structural or cosmetic reasons it could be permanent.

 

[frenchy85]

That's exactly what I would like to do. I would like to reline it with single wall stainless steel. Sorry I should have been more clear in my original post.

 

[fixit1960]

That's exactly what I would like to do. I would like to reline it with single wall stainless steel. Sorry I should have been more clear in my original post.

I see no reason why you couldn't. The single wall SS inside of the clay liner inside of the brick and mortar, I wouldn't have any concerns safety wise. 6" stainless should fit fine inside of the clay liner saving you the trouble of braking it out. The bottom elbow and a portion of the clay liner at the very bottom will have to be removed to allow access to the elbow joint. Install the tee if you want at the bottom to have access underneath for a cleanout. 18.5 ft will take 6 sections and the tee should bring you to the top. When I installed my 2 different stacks you could buy it in 3 ft lengths. Buy stainless steel screws to attach sections with. May have to brace up the bottom to help support the weight of the pipe. I set a plate and capped the top of the chimney opening and dri-creted a cap around it to center and help support it. You can also Dri -crete the opening at the bottom coming into your basement to seal it up and support the tee coming off the elbow coming into your basement. My stack in the house was 33 ft tall.

Good luck...

 

[Tjcole50]

You may not have room for an insulated liner being only 6.5 on your clay. They make a cone you can attach to the end of your liner and a helper can pull from the bottom with a line attached to the cone. I did my own 6" liner on a 25 ft exterior masonry chimney really was easy. Even without insulation having a liner is better than brick or oversized clay flue alone. I have a secondary chimney that goes to my basement. It is a 6.5" clay liner. I'm going to drop a 6" non insulated flex liner down it as well and add another stove. Flex liners are fine and most are garuntee for life. I got mine from chimney liner depot quick shipping and good customer service. Being your a carpenter this is a task you can easily handle you will laugh at how easy it is once your finished. Also the flex liner I bought was a kit. Came with collar 25' of flex rain cap top plate etc.

 

[fixit1960]

You may not have room for an insulated liner being only 6.5 on your clay. They make a cone you can attach to the end of your liner and a helper can pull from the bottom with a line attached to the cone. I did my own 6" liner on a 25 ft exterior masonry chimney really was easy. Even without insulation having a liner is better than brick or oversized clay flue alone. I have a secondary chimney that goes to my basement. It is a 6.5" clay liner. I'm going to drop a 6" non insulated flex liner down it as well and add another stove. Flex liners are fine and most are garuntee for life. I got mine from chimney liner depot quick shipping and good customer service. Being your a carpenter this is a task you can easily handle you will laugh at how easy it is once your finished. Also the flex liner I bought was a kit. Came with collar 25' of flex rain cap top plate etc.

You are right, but we were talking about using a single wall rigid 6 " SS liner. No reason to have an insulated liner. It will set inside of the clay and that sets inside of the brick and mortar. Kinda overkill to begin with. It will save him having to remove the clay liner and he won't have to worry about his stack cooling off too soon and creating creosote. Should fit okay.

 

[laynes69]

Technically if the Terra cotta is cracked, the new liner going in should be insulated. When a liner cracks, creosote gets behind the liner, and there's also buildup within the liner that has to be removed. A single wall liner will still transfer heat to the existing liner, therefore insulation keeps from igniting anything behind it, and blocks heat from the structure. If the existing chimney was swept well and the tiles were in good shape, no insulation would be required.

 

[fixit1960]

Technically if the Terra cotta is cracked, the new liner going in should be insulated. When a liner cracks, creosote gets behind the liner, and there's also buildup within the liner that has to be removed. A single wall liner will still transfer heat to the existing liner, therefore insulation keeps from igniting anything behind it, and blocks heat from the structure. If the existing chimney was swept well and the tiles were in good shape, no insulation would be required.

Okay, I'm not following why the new SS liner would have to be insulated. Insulated liners are meant to be used when placed in or next to combustible building products, wood, roofing material, drywall and such. Did I miss something or is this existing set up not a clay liner inside of a brick and mortar chimney? If so there is no need for the extra expense of the insulated SS. And no safety reason either. IMO. . Lets see if the OP can clear that up. I reread his post and it does not say the clay liner is inside a brick and mortar structure, but if not, what is it in?

 

[laynes69]

Not knowing what's behind the existing liner, I personally wouldn't chance it. The odds of getting a rigid 6" liner down a 6.5" flue will be slim, unless the existing tiles are lined up perfectly and there's no mortar sticking out between the joints. We had a 7x11 chimney, and I had to go 5.5" rigid to fit within the chimney. For piece of mind and safety, I poured vermiculite around the liner to insulate it, then capped the masonry chimney with stainless.

 

[fixit1960]

Not knowing what's behind the existing liner, I personally wouldn't chance it. The odds of getting a rigid 6" liner down a 6.5" flue will be slim, unless the existing tiles are lined up perfectly and there's no mortar sticking out between the joints. We had a 7x11 chimney, and I had to go 5.5" rigid to fit within the chimney. For piece of mind and safety, I poured vermiculite around the liner to insulate it, then capped the masonry chimney with stainless.

I see your argument. The main concern for me would be actually getting the 6" stainless down the run. It might be tight, I can't imagine the terra cotta being that misaligned but there's a chance. I would have thought if it had been that misaligned he would have mentioned it in his post. Knowing that a possible fix may involve trying to stuff something larger down the run. As far as a safety issue in the event that some creosote built up behind the cracked portion... I would not have concerns with that. It takes flame to light off the creosote. If the liner is installed and joined and fastened properly there will be no chance of flame ever hitting it. With the terra cotta still in place that is an additional amount of non conducting insulation. The way I read it, it is a crack, not a missing chunk .

It will be up to the OP to decide what he is comfortable with . Has the way I'm describing been done in the past safely? Yes. Is your way wrong, absolutely not, he was asking for a cheaper, easier way to do it and still maintain his margin of safety. I think the way I described will do that. I have done the same in my home and not had an issue for 30 years.

It will be interesting to see what he actually does....

 

[Mad Professor]

Not knowing what's behind the existing liner, I personally wouldn't chance it. The odds of getting a rigid 6" liner down a 6.5" flue will be slim, unless the existing tiles are lined up perfectly and there's no mortar sticking out between the joints. We had a 7x11 chimney, and I had to go 5.5" rigid to fit within the chimney. For piece of mind and safety, I poured vermiculite around the liner to insulate it, then capped the masonry chimney with stainless.

I had to line a 8 X 12" O.D. clay flue in a masonry/brick chimney. Best solution was an ovalized flexible liner that would still fit with the wrap on insulation.

 

[frenchy85]

I'm going to use 6" rigid single wall. I should have everything by this weekend, and install it on Saturday. I need to it's getting cold in here, haha. I can just reach the crack from inside, so I will clean it up and patch it the best I can with refractory cement. I know it will be a tight squeeze but I do not want to have to go down to 5.5" or 5".

 

[fixit1960]

I'm going to use 6" rigid single wall. I should have everything by this weekend, and install it on Saturday. I need to it's getting cold in here, haha. I can just reach the crack from inside, so I will clean it up and patch it the best I can with refractory cement. I know it will be a tight squeeze but I do not want to have to go down to 5.5" or 5".

I believe you have made the most economical and fastest fix decision. I truly don't have any concerns safety wise. Stainless liner installed properly is bullet proof. Remember to use stainless steel screws. Good luck.

 

[taskswap]

Just to clear up a point here, there's a lot of helpful advice... but insulation is NOT for protection. A half-inch of insulation and aluminum foil will do absolutely zero to stop the heat of a chimney fire from reaching your brick. Its purpose is for performance - you want that flue gas to stay as hot as possible all the way up, both to provide the best draft and to minimize creosote condensation on the walls. If you have an interior chimney, it's not as big of a deal, but EVERY resource I consulted when I did my own (tw0) strongly recommended insulating the liner in an external chimney, which I have.

@frenchy85 it sounds like you've got your plan all sorted out... I'm just posted this for the archives. Best of luck!

 

[Tjcole50]

Insulation does help performance for sure but on a 6x? Terra cotta fitting a 6" liner down with an insulation blanket plus lock wire is a *****. A liner period is a must and is much better performing and safer than plain ol clay. Either way lining is a step in the right direction for sure

 

[Wisneaky]

Just to clear up a point here, there's a lot of helpful advice... but insulation is NOT for protection. A half-inch of insulation and aluminum foil will do absolutely zero to stop the heat of a chimney fire from reaching your brick. Its purpose is for performance - you want that flue gas to stay as hot as possible all the way up, both to provide the best draft and to minimize creosote condensation on the walls. If you have an interior chimney, it's not as big of a deal, but EVERY resource I consulted when I did my own (tw0) strongly recommended insulating the liner in an external chimney, which I have.

@frenchy85 it sounds like you've got your plan all sorted out... I'm just posted this for the archives. Best of luck!

I'd like to know where you get your information? You can touch my double walled and insulated liner and it is just warm. Can you do that with single walled pipe? No you can not. Insulation for one does not burn. So yes it is for protection. Get your facts straight before you post something.

 

[brenndatomu]

Just to clear up a point here, there's a lot of helpful advice... but insulation is NOT for protection. A half-inch of insulation and aluminum foil will do absolutely zero to stop the heat of a chimney fire from reaching your brick.

Wrong wrong wrong! That is exactly what it is for! Ceramic insulation blanket with (or without) foil backing makes a HUGE difference in heat transfer. Almost all furnaces have it, I'd venture to say all cars have some, used in TONS of industrial applications, I'm sure I am forgetting dozens of applications.
Many people pony up the extra money for the insulation because of the performance gains but if you do some investigation on code requirements when installing a liner...you'll find that most liner installs must have insulation...for safety. About the only time insulation is not required is if you have a very large flue and can get proper clearance, which most chimneys are not big enough to accommodate. Even if the chimney is big enough to get the clearance needed, it is almost impossible for the average person (and many pros) to get and keep the liner centered due to normal expansion/contraction of the liner, hence, code required insulation.

 

[fixit1960]

Wrong wrong wrong! That is exactly what it is for! Ceramic insulation blanket with (or without) foil backing makes a HUGE difference in heat transfer. Almost all furnaces have it, I'd venture to say all cars have some, used in TONS of industrial applications, I'm sure I am forgetting dozens of applications.
Many people pony up the extra money for the insulation because of the performance gains but if you do some investigation on code requirements when installing a liner...you'll find that most liner installs must have insulation...for safety. About the only time insulation is not required is if you have a very large flue and can get proper clearance, which most chimneys are not big enough to accommodate. Even if the chimney is big enough to get the clearance needed, it is almost impossible for the average person (and many pros) to get and keep the liner centered due to normal expansion/contraction of the liner, hence, code required insulation.

I agree that the insulation is for protection purposes. That being said, an insulated liner inside a clay liner, inside of a solid brick and mortar chimney in good condition it is overkill and in my opinion un-necessary. The way I understand the OP, he has a clay liner inside of a brick and mortar chimney and now you want him to put an insulated stainless steel liner inside of that . If its' that dangerous maybe we should all quit burning solid fuel. Come on guys, you are gonna confuse the OP. The insulated liner was meant to run inside of wood structures with ample air space where no existing brick and mortar structure exists. Or where the integrity of the brick and mortar structure is suspect. It is beneficial in some cases to utilize an insulated liner in cases where you have a exposed exterior chimney that would allow for an uninsulated to cool to the point you have flue gas cooling and depositing creosote. I don't think that is his case...