Need help with a 9" chimney width

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kinatron

New Member
Sep 26, 2014
7
Western Washington
We just replaced a malm firedrum freestanding fireplace which connected to our 9" chimney, with an 6" Englander stove.
I've been having a hard time finding a 6' to 9" adapter. In calling the local stove shops nobody says that anyone makes a 9" chimney. The Chimney is a 3 walled 9" Duravent chimney that's probably as old as the house (1980) but I can't find anything on the duravent website about 9" chimneys.

Does anybody know of any woodstove 6" to 9" adapters?

I did find a 6" to 9" 'stovepipe' reducer but when it arrived it looks like its made from galvanized steel which I'm hesitant to use with a wood stove (poisonous zinc oxide gases)

Any suggestions?
Does anyone think I should just use adapter I already have?


Here's a picture of the outside of the chimney (it's housed in a wooden chase) [Hearth.com] Need help with a 9" chimney width

Here's the stove chimney and current (I believe galvanized) adapter.
[Hearth.com] Need help with a 9" chimney width

Here's a close up of the adapter I bought online as a "stovepipe" adapter.
the label says (broken link removed to http://www.essentialhardware.com/imperial-manufacturing-gv12699x6-311p-galvanized-increaser-9-x-6-236646.html)
((broken link removed to http://www.essentialhardware.com/imperial-manufacturing-gv12699x6-311p-galvanized-increaser-9-x-6-236646.html)
[Hearth.com] Need help with a 9" chimney width

And here's the chimney the inner pipe is 9" The outside chimney is also 9"

[Hearth.com] Need help with a 9" chimney width
 
Call Duravent and ask whether the chimney is listed to be connected to a woodstove. If that is not the case, you need to clean it well and drop a 6" insulated liner down there.
 
That appears to be air-cooled pipe. If so it is rated for lower temperature use than a wood stove and will have to be replaced with 6" class A chimney pipe before a wood stove can be connected, or as Grisu suggested, have a 6" liner installed.

But first, the pipe should not be in direct contact with sheetrock and should not terminate flush with the wall. It would be good to investigate and see if this thimble is safely installed. It doesn't appear to be. Regardless, lose the plastic tape patching around the pipe. It looks ready to catch fire.
 
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The pipe is not in contact with the sheet rock. The "tape" you see is paper I tucked into the seam to keep spiders out, while I'm figuring out how to install this sucker. I actually have a role in insulation in the pipe right now.

So it looks like I need to do the 6" liner, I was already thinking I might need to do that.
I have a question about the liners. Everything online references liners for masonry chimneys, are they ever run into existing chimneys, like in my situation?
It seems like it should be pretty straightfoward (or downward in this case) but I just don't see anyone doing this in an existing chimney.

Will I also need to insulate the liner as well, or will the air cooling pipe be sufficient?

What do you guys recommend rigid or flexible liners?

The chimney is a straight shoot about 20 ft long with the tee into the house, and I have about 4' to work with under the chase? Can I install this from the bottom, or is it always done from the top? Is this a DIY project or should I follow my wifes advice and hire a professional

Thanks again for your help.
 
Class A pipe thru the wall needs to be 9" from any drywall and any other combustible like studs. I'm not sure what the ruling is for this old air cooled pipe, but I would think that it would be at least the same. It isn't recognized as a valid thimble shield for the single wall liner that will be coming thru the pipe. Insulating it is a good idea though this is untested territory afaik. There is still the issue of shielding as it enters the room. It would be best to get a csia or ncsg certified sweep there to determine safe options. There may be more issues we are not seeing.
 
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begreen and Grisu
I called DuraVent and they said the chimney is obsolete and recommended a new chimney... and stated they are not listed to run vent in vent. Convenient advice from a chimney retailer

I had a chimney sweep stop by house. He described the chimney as an older pre-manufactured class A chimney that would be fine for wood use and probably didn't even need a liner as he described the air cooling convection properties. Given draft issues I still want to go with an insulated liner I called a fireside chimney supply and the technician said that chimneys sweeps assessment probably isn't correct. That most air cooled chimneys are not class A and the chimney isn't rated at the same level as the liner and therefore violates safety codes. Arrgggg. He went on to say that many people do install insulated liners into prefab chimneys but that he couldn't recommend it per codes.

I have a hard understanding how a chimney that we've been using (albeit very lightly) with a freestanding fireplace would still pose a danger with a 6" insulated liner added.
With a new woodstove we do plan on using the woodstove much more and I suppose it will have higher temperatures, but I don't see any safety issues running the liner through the existing chimney.

What do you guys think?
Do you guys have any experience with pre-insulated liners?
http://www.firesidechimneysupply.co...flex-pre-insulated-chimney-liner-tee-kit.html

thanks for your help
 
The chimney pipe company gave you an honest response. It was not to sell you new pipe. They have no idea what brand it will be replaced with.

FWIW, I'll bet that sweep was not csia certified.
 
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What do you guys think?
Do you guys have any experience with pre-insulated liners?
http://www.firesidechimneysupply.co...flex-pre-insulated-chimney-liner-tee-kit.html

thanks for your help
I just installed a smooth wall liner from the same company (FiresideChimney). It is a good quality item. I did the 1/2 insulation wrap. Not hard to do.

I just looked at that new pre-insulated system you posted.....looks nice!:)
Wish they had that last year when I bought mine,:( I may have used it instead.
 
With a new woodstove we do plan on using the woodstove much more and I suppose it will have higher temperatures, but I don't see any safety issues running the liner through the existing chimney.

Probably not a safety issue but defiantly a liability issue. If i was doing the job i would tear it out and install new for sure.
 
No when I pressed the sweep it he told me he let his certification expire... The guy was a character though black pea coat and fedora hat. He looked the part and seemed knowledgeable but not certified.

I did hear back from Duravent, credit them for calling me back. He said that my current chimney was rated for woodstoves prior to ~1987 and rated at 1700 degrees. Newer stoves need to be rated at 2100. He actually said that I should be fine with an insulated liner but couldn't officially back that up because those chimneys were never tested in that configuration.

Guys I think I'm going with the liner (bholler has me a little worried) I've got family and of course safety first, but with an insulated liner I'm feeling pretty confident.

What do you guys think :)
 
No when I pressed the sweep it he told me he let his certification expire... The guy was a character though black pea coat and fedora hat. He looked the part and seemed knowledgeable but not certified.

I did hear back from Duravent, credit them for calling me back. He said that my current chimney was rated for woodstoves prior to ~1987 and rated at 1700 degrees. Newer stoves need to be rated at 2100. He actually said that I should be fine with an insulated liner but couldn't officially back that up because those chimneys were never tested in that configuration.

Guys I think I'm going with the liner (bholler has me a little worried) I've got family and of course safety first, but with an insulated liner I'm feeling pretty confident.

What do you guys think :)


Not an expert by any stretch but here's what I'm thinking.
I don't doubt the two systems together wouldn't do the job even though neither is designed to work together.
My concerns would be maintaining the insulative properties at the thimble connection and what type of insulated thimble can be modified to work with the dura flex piping? That will be the weak point or more aptly the hot point in your setup.

Also not a stove expert but personally I'd feel better running a cat stove in such a setup which generally to my knowledge burns a cooler pipe. No expierience with the NC 30 but I,m betting they burn hot or at least hotter at the pipe as a secondary burn only stove. It's a big one at that which leaves more room for excessive heat build up if you forget to regulate the air before leaving for work.

Bottom line, I think it can work but I'd want to make sure it's done right. The connection at the thimble will be key IMO.
 
I totally agree with jo191145 the wall pass thu area is what really concerns me I dont doubt that an insulated liner in the rest of the chimney would work but i would at least open up around that pipe going through the wall to chech it out it looks scary to me
 
that piece for reducing is galvanized Iknow I'm a galvanizer .might be good with fireplace but wood stove burns hotter in pipe,don't risk it
 
Metal chimneys are fine for camps and occasional fires but for a home, a masonry chimney, its a bit more but but you are better served by it,pellet stoves are a different matter.

Howdy neighbor ... when you talk about "metal chimneys" are you talking about Class A chimneys (i.e. Metalbestos)?
 
Howdy neighbor ... when you talk about "metal chimneys" are you talking about Class A chimneys (i.e. Metalbestos)?
Big howdy back yep class A in my humble opinion of premium quality is safe don't get me wrong but it's cost is just slightly under what you can put in for an 8 X 8 block n tile brick top chimney I say spend the extra and get something that will compliment your home.A chimney is one of the most important functional items in a home. Stay warm my friend
 
Personally I would prefer to have a good quality class A chimney system in my home. It's easier to install interior wise being ceiling supported and has tested and respected clearances. Add to that no worries about mortar or tiles failing over time, and a correctly sized round, insulated pipe all the way up for better draft and cleaning.
 
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Personally I would prefer to have a good quality class A chimney system in my home. It's easier to install interior wise being ceiling supported and has tested and respected clearances. Add to that no worries about mortar or tiles failing over time, and a correctly sized round, insulated pipe all the way up for better draft and cleaning.

I have chimneys that I have constructed and been there 40 years.Take it some liners fail but it's usually a moisture problem with no cap or a poorly kilned liner.Metalbestis problems was it's insulation between the walls would fail and lose its insulating properties in time and the connections are areas for creosote buildup.But it's like comparing apples to oranges.A nice piece of masonry coming out your beautiful home or the tin man's hat.
 
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I'm with the stainless steel man and his hat. Masonry failed during the last earthquake. No issues with the stainless pipe.
 
We all have our likes I'm a Mason so I might be partial to my craft.You must live in Ca.We here in New England like things that last ,if you like visit (broken link removed)


Another mason here. Pleased to meet ya.

Some worry about chimney fires. I welcome them. Haven't run a brush down my wood furnaces 8x12 flue since 1994.
Dry wood helps but if I notice the draft lessening I'll force the issue. :)
 
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Same here creosote is the enemy.People try to get all they can out of there fires so they choke their fires, small smoldering fires are bad a good hot fire will burn cleaner and not leave a tar buildup.Condensation also creates a problem.Nice to meet ya
 
Same here creosote is the enemy.People try to get all they can out of there fires so they choke their fires, small smoldering fires are bad a good hot fire will burn cleaner and not leave a tar buildup.Condensation also creates a problem.Nice to meet ya
Ok guys i work on both types all the time and while i prefer the look of a good masonry chimney the performance comparison is hugely in the favor of an insulated ss lined chimney either prefab or lined masonry. If price was not an issue i would always do masonry lined with an insulted heavy wall ss liner it gives you the best of both worlds. I know for a fact most clay lined chimneys that we line with ss the people comment that they had no idea how much better their stove could run. But i do absolutely agree with you about chocking down the fire being one of the worst things you can do right up there with burning wet wood.
 
Some worry about chimney fires. I welcome them.
What really? that is a great attitude when was the last time you dropped a camera and checked that liner for cracks? And did you build it with the proper clearance to combustibles from the outside of the masonry?
 
What really? that is a great attitude when was the last time you dropped a camera and checked that liner for cracks? And did you build it with the proper clearance to combustibles from the outside of the masonry?


Normal 2" clearance against the house, 4" solid block, another 2"of internal clearance then another 4" support wall before you find the flue. External walls 8" of fieldstone. You'll have to forgive me if I'm fearless. I needed all that room to satisfy building codes for the large throat of the fireplace. External Chimney has 32" of depth. Not your average build. I built all the fear right out of it. :)
 
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