Venting wood stove into existing masonry chimney

[gdamats]

Hello all,

I have an existing masonry fireplace, chimney on the exterior of the home. I purchased a wood stove and I am looking at options to begin using it sooner rather than later. In the spring, I plan to put a more permanent venting solution in place, but I'm wondering if for the remainder of this winter if it is safe to just use a few pieces of single wall stove pipe, and vent right into the chimney (vs running something all the way to the top of the chimney). The stove will sit inside my fireplace and sits just a few inches from the existing flue. That said, there will only be a few inches of stove pipe that will be exposed coming out of the stove, the rest will be inside of the chimney. Could I just assemble a few feet of single wall stove pipe and vent it into the chimney to get me through the rest of this winter?

 

[bholler]

Hello all,

I have an existing masonry fireplace, chimney on the exterior of the home. I purchased a wood stove and I am looking at options to begin using it sooner rather than later. In the spring, I plan to put a more permanent venting solution in place, but I'm wondering if for the remainder of this winter if it is safe to just use a few pieces of single wall stove pipe, and vent right into the chimney (vs running something all the way to the top of the chimney). The stove will sit inside my fireplace and sits just a few inches from the existing flue. That said, there will only be a few inches of stove pipe that will be exposed coming out of the stove, the rest will be inside of the chimney. Could I just assemble a few feet of single wall stove pipe and vent it into the chimney to get me through the rest of this winter?

Well have you had the existing flue inspected to see what condition it's in? Is it sized properly forr the stove? Does the chimney have the required clearances from the outside of the masonry structure to combustible materials? Can you make a positive connection to the existing flue?

If the answer to any of those things is no then no you can't. Why not just install a liner now?

 

[Ashful]

bholler is the chimney professional, so take his advice. But there's a few more things that can be added, which depending on your experience, you may or may not already know:

Modern EPA-compliant stoves are far more efficient than their predecessors, and that efficiency is achieved by putting much less heat up the flue. A flue must be kept warm to draft consistently and to prevent the formation of creosote in the chimney, and it is likely a modern stove will have insufficient heat going up the flue to achieve this at most settings. Creosote is carried by water vapor, and condensation (by cooling) of that water vapor is the primary mechanism of creosote deposition within the flue. So, methods that worked fine for many generations of older stoves, in which the creosote-bearing water vapor was safely ejected from the top of a well-drafting chimney, can fail with a more efficient modern stove.

So, even if the answers to each of bholler's questions above are "yes", meaning you can legally plumb a stove into an existing flue, there is good reason to consider doing otherwise. The standard approach today, even in the case of a passable flue, is to drop a 6" flexible stainless liner down thru the existing flue, and this can be a relatively easy DIY job (with plenty of advice available on this forum) for most with reasonable skills, roof height, and pitch.

 

[gdamats]

Thank you both. The existing chimney is stone exterior and I believe it's 12x12 clay inside, about 14 years old. I was trying to avoid going on the roof during this weather and am trying to understand if there are any feasible options so that I can use my stove for the remainder of the winter until I'm able to safely install a more permanent solution. The single wall black pipe is fairly inexpensive when comparing to the stainless liner but I understand that it's not supposed to exceed 10' and I would need about 17'. What other options are available? 18' of single wall black pipe from Menards costs about $60, the stainless liner kit is about $550. Is the stainless liner really necessary?

 

[bholler]

Thank you both. The existing chimney is stone exterior and I believe it's 12x12 clay inside, about 14 years old. I was trying to avoid going on the roof during this weather and am trying to understand if there are any feasible options so that I can use my stove for the remainder of the winter until I'm able to safely install a more permanent solution. The single wall black pipe is fairly inexpensive when comparing to the stainless liner but I understand that it's not supposed to exceed 10' and I would need about 17'. What other options are available? 18' of single wall black pipe from Menards costs about $60, the stainless liner kit is about $550. Is the stainless liner really necessary?

Yes a stainless liner is nessecary. And insulation on it probably is as well. Black pipe cannot go inside a chimney and it wouldn't last more than a year or 2 anyway.

 

[gdamats]

Yes a stainless liner is nessecary. And insulation on it probably is as well. Black pipe cannot go inside a chimney and it wouldn't last more than a year or 2 anyway.

Understood @bholler , thank you. When you say insulation, are you referring to the stainless liner with insulation built in (about $1k) or the stainless liner with separate insulation wrapped on it?

 

[bholler]

Understood @bholler , thank you. When you say insulation, are you referring to the stainless liner with insulation built in (about $1k) or the stainless liner with separate insulation wrapped on it?

Either pre insulated or wrapped on site is fine

 

[EbS-P]

Do it right the first time.



I have seen videos of pushing the liner up from the bottom, but you have to get up there to instal top plate and cap.

I used the wrap from rockford. It was simple. if your flue is straight its easy enough to drop it right in.

 

[bholler]

I installed 3 liners last week with snow and ice.

 

[stoveliker]

I installed 3 liners last week with snow and ice.

Lol, I thought rockwool worked better than snow and ice to insulate a liner ;-)

 

[Ashful]

Thank you both. The existing chimney is stone exterior and I believe it's 12x12 clay inside, about 14 years old. I was trying to avoid going on the roof during this weather and am trying to understand if there are any feasible options so that I can use my stove for the remainder of the winter until I'm able to safely install a more permanent solution. The single wall black pipe is fairly inexpensive when comparing to the stainless liner but I understand that it's not supposed to exceed 10' and I would need about 17'. What other options are available? 18' of single wall black pipe from Menards costs about $60, the stainless liner kit is about $550. Is the stainless liner really necessary?

The short flue is a plus from the perspective of condensation, but a big minus on draft pull (eg. water column). Moreover, 12x12 is an awful big clay cross-section to heat in an exterior chase, with the little available waste heat from any modern stove. You might be able to make it work, but even if so, you would likely be severely limited in how far you can turn the stove down before cooling causes troubles. You'd also likely want to get onto the roof to do inspections (and potentially cleanings) every few weeks, if you're running a setup like that.

Given that most of IL gets the occasional warm weekend in February, and will likely be out of snow and ice for the year in another 6-7 weeks, I'd not be looking to shortcut this, unless there's a severe hardship forcing it. Use the next few weeks to pick and order the components you're going to need, and then try to catch a warm day or three in February to execute the installation. Most work can be done from a ladder or from below, in most cases, or you can hire a pro (like bholler) to work with you and handle the parts with which you have the least comfort.

 

[gdamats]

Thank you all for the help! You've convinced me not to short-cut this, so I swept the chimney and ordered and already installed a Forever Vent SS liner with the insulation from Rockford. I timed it well enough so that I went up on the roof yesterday when almost all of the snow had melted and just before tonight's blizzard that's about to hit us . I've cut a piece of steel to act as my new flue cover and plan to place a few pieces of rockwool insulation on top of it. A couple of questions for you all...

Can the flex vent connect directly to the stove or should I plan to use the SS connector? I would think using the connector would be easier anyway since it's a clean ring and gives me a little more play to fit it in place. Should I only secure the connections (with 3 sheet metal screws or should these connections be sealed with a high temp sealer/silicone?

 

[begreen]

You will want to use an appliance adapter meant for flex liner. These have a large band clamp to secure the liner. This is much better than screwing into the thin metal. They come in straight vertical adapter or small angle elbows (15º & 30º).

Flue Liner Appliance Connector - Product Info | Rockford Chimney Supply - Rockford Chimney

Our stainless steel chimney liner Vertical Appliance Connector joins flexible chimney liner to an appliance, fireplace, stove, or rigid liner pipe.

www.rockfordchimneysupply.com

 

[gdamats]

You will want to use an appliance adapter meant for flex liner. These have a large band clamp to secure the liner. This is much better than screwing into the thin metal. They come in straight vertical adapter or small angle elbows (15º & 30º).

Flue Liner Appliance Connector - Product Info | Rockford Chimney Supply - Rockford Chimney

Our stainless steel chimney liner Vertical Appliance Connector joins flexible chimney liner to an appliance, fireplace, stove, or rigid liner pipe.

www.rockfordchimneysupply.com

Thanks! The stainless connector that was in my picture is the appliance connector that came with the flex liner which did come with a couple of band clamps. That said, I will band clamp the flex liner to the vertical appliance adapter in my picture, then I will screw the appliance adapter to the stove, is that correct? As you can see from my picture, the stove is about 1/4" thick steel so I wouldn't be able to use a band clamp there, I would only be able to screw it in. Should I use foil tape around the seams to ensure that it's all sealed up?

 

[COOT]

Well have you had the existing flue inspected to see what condition it's in? Is it sized properly forr the stove? Does the chimney have the required clearances from the outside of the masonry structure to combustible materials? Can you make a positive connection to the existing flue?

If the answer to any of those things is no then no you can't. Why not just install a liner now?

Hey Bholler, Though this tad long hope you can help sounds like your smart s.o.b. with wood Been searching this forum someone else who asked this question not thrilled with the answers. Throw rocks at me but can't hurt ask anyway. Raised on my folks farm old school been heating off wood entire life. Our current ranch in boonies no restrictions all our buildings, 8 man Finn wood sauna, etc. with wood stoves all tied to huge beautiful perfect condition over built 12X12 flue proper height masonry chimneys, our living room big old wood guzzling Garrison One wood stove in front of fireplace piped into damper replacement sealed plate, about 40 cords out back via our harvested land don't pay anything for it, put the wood to her for 30+ years kicks ass, light her in Fall, warm up chimney, set the air, put wood to her 24/7 until Spring, other than annual chimneys sweeps, no maintenance no bullshit. Come Spring I run all our other stoves hot careful controlled chimney fires burn off any creosote, not so much as hairline crack in my clay liners, sweep chimney's ready for another year. Wife decides time for living room upgrade w/glass doors. Me: Just make sure what ever you order has horizontal vent, big firebox, secondary burn like our other secondary burn no cat stoves run fine direct w/no liner to our masonry chimney's . Truck pulls up delivers a Jotul V3, (she THOUGHT no cat) , real pretty but more I'm finding out about this damn thing already want bring it to dump toss off back my truck. Call me idiot but now catching up all this EPA crap, literally gotta be damn rocket scientist, moisture meters, perfect draft, reline chimney in our case gouging stove contractors want $1,500, annual maintenance, cleaning and/or intervals having replace cat relying on dealer for big $ parts, etc., etc. WTF !?!? Anyway I could care less efficiency this damn thing. Either hooking it up like all our other old one's or to dump it goes. Called old lifetime wood burning family friend she sez "bought my Oslo in '99, no cat, hooked to her proper height 12 X 12 flue masonry chimney w/ secondary burn, no cat, (though recommended at the time): she opted out of 6 inch reline, putting wood to her all Winter 24/7 since no problem". My researching Oslo F500 she has, from what I see both stoves the same except Jotul in the V3 got rid of the wider secondary tubes putting in more compact triple secondary burn to accomodate the (friggin) cat above it in combustion chamber. Last hope is my understanding is w/o cat will run like the F500 with hopefully enough heat loss keep the masonry chimney w/no liner draft going otherwise unless somehow I figure out how get that new girl operate like the old wood lovin girls,off to dump her $3,500 pile chit ass goes w/shopping for old school secondary burn rebuilt girl.

 

[bholler]

Hey Bholler, Though this tad long hope you can help sounds like your smart s.o.b. with wood Been searching this forum someone else who asked this question not thrilled with the answers. Throw rocks at me but can't hurt ask anyway. Raised on my folks farm old school been heating off wood entire life. Our current ranch in boonies no restrictions all our buildings, 8 man Finn wood sauna, etc. with wood stoves all tied to huge beautiful perfect condition over built 12X12 flue proper height masonry chimneys, our living room big old wood guzzling Garrison One wood stove in front of fireplace piped into damper replacement sealed plate, about 40 cords out back via our harvested land don't pay anything for it, put the wood to her for 30+ years kicks ass, light her in Fall, warm up chimney, set the air, put wood to her 24/7 until Spring, other than annual chimneys sweeps, no maintenance no bullshit. Come Spring I run all our other stoves hot careful controlled chimney fires burn off any creosote, not so much as hairline crack in my clay liners, sweep chimney's ready for another year. Wife decides time for living room upgrade w/glass doors. Me: Just make sure what ever you order has horizontal vent, big firebox, secondary burn like our other secondary burn no cat stoves run fine direct w/no liner to our masonry chimney's . Truck pulls up delivers a Jotul V3, (she THOUGHT no cat) , real pretty but more I'm finding out about this damn thing already want bring it to dump toss off back my truck. Call me idiot but now catching up all this EPA crap, literally gotta be damn rocket scientist, moisture meters, perfect draft, reline chimney in our case gouging stove contractors want $1,500, annual maintenance, cleaning and/or intervals having replace cat relying on dealer for big $ parts, etc., etc. WTF !?!? Anyway I could care less efficiency this damn thing. Either hooking it up like all our other old one's or to dump it goes. Called old lifetime wood burning family friend she sez "bought my Oslo in '99, no cat, hooked to her proper height 12 X 12 flue masonry chimney w/ secondary burn, no cat, (though recommended at the time): she opted out of 6 inch reline, putting wood to her all Winter 24/7 since no problem". My researching Oslo F500 she has, from what I see both stoves the same except Jotul in the V3 got rid of the wider secondary tubes putting in more compact triple secondary burn to accomodate the (friggin) cat above it in combustion chamber. Last hope is my understanding is w/o cat will run like the F500 with hopefully enough heat loss keep the masonry chimney w/no liner draft going otherwise unless somehow I figure out how get that new girl operate like the old wood lovin girls,off to dump her $3,500 pile chit ass goes w/shopping for old school secondary burn rebuilt girl.

I have no idea what the question there is

 

[kborndale]

I have no idea what the question there is

I couldn't even read the hole post, it gave me a headache.

 

[Ashful]

I have no idea what the question there is

Well, I stopped reading when he said you’re smart. 😆

But you made me go back and look for a question. I think I found it:

WTF !?!?

 

[Todd]

Looks like he’s trying to get a Jotul F500 v3 without the cat to operate in his 12x12” masonry chimney like his old Garrison did? Gonna need a liner.

 

[bholler]

Hey Bholler, Though this tad long hope you can help sounds like your smart s.o.b. with wood Been searching this forum someone else who asked this question not thrilled with the answers. Throw rocks at me but can't hurt ask anyway. Raised on my folks farm old school been heating off wood entire life. Our current ranch in boonies no restrictions all our buildings, 8 man Finn wood sauna, etc. with wood stoves all tied to huge beautiful perfect condition over built 12X12 flue proper height masonry chimneys, our living room big old wood guzzling Garrison One wood stove in front of fireplace piped into damper replacement sealed plate, about 40 cords out back via our harvested land don't pay anything for it, put the wood to her for 30+ years kicks ass, light her in Fall, warm up chimney, set the air, put wood to her 24/7 until Spring, other than annual chimneys sweeps, no maintenance no bullshit. Come Spring I run all our other stoves hot careful controlled chimney fires burn off any creosote, not so much as hairline crack in my clay liners, sweep chimney's ready for another year. Wife decides time for living room upgrade w/glass doors. Me: Just make sure what ever you order has horizontal vent, big firebox, secondary burn like our other secondary burn no cat stoves run fine direct w/no liner to our masonry chimney's . Truck pulls up delivers a Jotul V3, (she THOUGHT no cat) , real pretty but more I'm finding out about this damn thing already want bring it to dump toss off back my truck. Call me idiot but now catching up all this EPA crap, literally gotta be damn rocket scientist, moisture meters, perfect draft, reline chimney in our case gouging stove contractors want $1,500, annual maintenance, cleaning and/or intervals having replace cat relying on dealer for big $ parts, etc., etc. WTF !?!? Anyway I could care less efficiency this damn thing. Either hooking it up like all our other old one's or to dump it goes. Called old lifetime wood burning family friend she sez "bought my Oslo in '99, no cat, hooked to her proper height 12 X 12 flue masonry chimney w/ secondary burn, no cat, (though recommended at the time): she opted out of 6 inch reline, putting wood to her all Winter 24/7 since no problem". My researching Oslo F500 she has, from what I see both stoves the same except Jotul in the V3 got rid of the wider secondary tubes putting in more compact triple secondary burn to accomodate the (friggin) cat above it in combustion chamber. Last hope is my understanding is w/o cat will run like the F500 with hopefully enough heat loss keep the masonry chimney w/no liner draft going otherwise unless somehow I figure out how get that new girl operate like the old wood lovin girls,off to dump her $3,500 pile chit ass goes w/shopping for old school secondary burn rebuilt girl.

When was the last time anyone ran a camera through one of your chimneys? If you are burning the creosote out of your chimneys every year I can absolutely guarantee that there are cracked liners. There is no way around it. Oh and if one of those fires you lit caught the house on fire and someone found out, it would be classified as arson. That means no insurance settlement and possible jail time.

 

[COOT]

When was the last time anyone ran a camera through one of your chimneys? If you are burning the creosote out of your chimneys every year I can absolutely guarantee that there are cracked liners. There is no way around it. Oh and if one of those fires you lit caught the house on fire and someone found out, it would be classified as arson. That means no insurance settlement and possible jail time.

I think question directly asked violate terms of this forum. Inspect chimneys regularly. Hope was V3 w/o cat operate like (2008-2019) non cat F500 and/or V2. Good points if decide use stove will leave in cat and get liner or sell stove get rebuilt older model w/secondary burn that'll operate w/masonry chimney. Thanx 4 getting back.

 

[bholler]

I think question directly asked violate terms of this forum. Inspect chimneys regularly. Hope was V3 w/o cat operate like (2008-2019) non cat F500 and/or V2. Good points if decide use stove will leave in cat and get liner or sell stove get rebuilt older model w/secondary burn that'll operate w/masonry chimney. Thanx 4 getting back.

The old version won't work properly in a 12x12 clay liner either.

Asking questions certainly isn't against terms of use at all. People asking questions is pretty much what makes up this forum.


How do you inspect your chimneys regularly? I inspect hundreds a year and can tell you that you absolutely can't see most cracks or bad mortar joints at all without a camera in the chimney. Do your chimneys have the required clearance to combustibles from the outside of the masonry structure?

 

[COOT]

The old version won't work properly in a 12x12 clay liner either.

Asking questions certainly isn't against terms of use at all. People asking questions is pretty much what makes up this forum.


How do you inspect your chimneys regularly? I inspect hundreds a year and can tell you that you absolutely can't see most cracks or bad mortar joints at all without a camera in the chimney. Do your chimneys have the required clearance to combustibles from the outside of the masonry structure?

My guess was asking things related to altering EPA stoves , removing cats etc. maybe violation. Thanks for putting up w/rant. The mason we purchased ranch from, in part why we bought property, several huge over built beautiful chimneys through out house separate for furnace, 8 man Finn Sauna, furnace, etc. and chimneys in all the out buildings. The double flued for living room outside dimensions 5 feet deep by 8 feet wide is set on huge concrete footer thats located 10 feet below grade of full basement extending to proper height above roof has huge extended hearth to safely accommodate wood stove in front of fireplace. Creosote burns not every year, lot old timers it was common, carefully controlled just hot enough bubble the creosote for sweeping, not raging chimney fire crack liners, the liner's are fine. Again several folks we know had F500's direct to masonry no issues however others w/them had issues had to reline. However point you made very good game changer, we pay x-tra w/good carrier have all our stoves fully insured. Altering or not installing liner could void or create insurance issues. I'm just old school cantankerous wood burner many years all stoves hooked to masonry, literally no maintenance, no liners, no cats, throw any wood in them (other than fresh green), easily DIY sweep chimneys annually that's it.. We're leaning towards selling V3 get older rebuilt w/secondary burn like rest of our stove's. Again thanx so much.

 

[bholler]

My guess was asking things related to altering EPA stoves , removing cats etc. maybe violation. Thanks for putting up w/rant. The mason we purchased ranch from, in part why we bought property, several huge over built beautiful chimneys through out house separate for furnace, 8 man Finn Sauna, furnace, etc. and chimneys in all the out buildings. The double flued for living room outside dimensions 5 feet deep by 8 feet wide is set on huge concrete footer thats located 10 feet below grade of full basement extending to proper height above roof has huge extended hearth to safely accommodate wood stove in front of fireplace. Creosote burns not every year, lot old timers it was common, carefully controlled just hot enough bubble the creosote for sweeping, not raging chimney fire crack liners, the liner's are fine. Again several folks we know had F500's direct to masonry no issues however others w/them had issues had to reline. However point you made very good game changer, we pay x-tra w/good carrier have all our stoves fully insured. Altering or not installing liner could void or create insurance issues. I'm just old school cantankerous wood burner many years all stoves hooked to masonry, literally no maintenance, no liners, no cats, throw any wood in them (other than fresh green), easily DIY sweep chimneys annually that's it.. We're leaning towards selling V3 get older rebuilt w/secondary burn like rest of our stove's. Again thanx so much.

Ok I have been doing this a long time. I have seen a fair number of guys who "cleaned" their own chimneys by "controlled fires". Absolutely every one of them said their chimneys were perfect. Every one of them was destroyed when I put a camera in them. Yes I know burning out chimneys was common practice. It is also not even remotely safe every time you do it you are taking a big risk.

 

[COOT]

Ok I have been doing this a long time. I have seen a fair number of guys who "cleaned" their own chimneys by "controlled fires". Absolutely every one of them said their chimneys were perfect. Every one of them was destroyed when I put a camera in them. Yes I know burning out chimneys was common practice. It is also not even remotely safe every time you do it you are taking a big risk.

I'm sure your much more knowledgeable in this area. And for this reason felt was likely wise stop this practice having heard about some rotary brush was going to look into that supposed works in 12X12 masonry flues, is that true, if so any you'd recommend?