Routing a cookstove to a fireplace chimney

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pianoman8t8

Member
Jun 20, 2017
16
Maine
Hi everyone, new to the forum here. I've done a lot of searching, but haven't found an answer to my exact scenario and what I was thinking of doing.

A little context:
We have a 2-sided fireplace with a 12"x12" or 13"x13" flu. Kinda hard to get a super accurate measurement up there from outside the fireplace. On each side of the fireplace there are glass doors that open. The oil furnace is on a separate smaller flu nearby. Oh, and we get a metric ton of draft up that large flu. All winter long... sucks the heat right out. I went around the glass door frame with some gasket rope to try and seal it up a bit more last winter (1st winter in this house). I noticed a drop in draft coming through the front door weather stripping after doing this. When having a fire in the fireplace, it roars pretty good, almost too much. Sucks it up so fast, there's occasionally embers coming out the top of the chimney! Not exactly proud of that... And there is no damper plate. There's a rod for one, but no plate on the end of it, the rod ends flush with the inside of the flu.

Here's my thought... Since I get so much draft, I was wondering if I could run a 6" chimney liner for the cookstove from one side, and either leave the other side open for the fireplace still, or run 2 chimney liners (since there's ample room for 2 6" liners) in the same flu: 1 for the cookstove, and 1 for a regular wood stove as primary heat instead of burning oil. I couldn't find anything about running 2 liners in 1 flu anywhere in the code, could be because nobody ever really does this since flues would otherwise not be big enough...

If I can't leave the other side of the fireplace usable, I may not opt to do this as it would be a shame to hook something up on one side and the other side just be empty and unusable. It's a pretty sizeable fireplace overall. There's about 4-5ft between the opposing glass doors. One side faces the kitchen with stone tile floor, and the other faces the living room. Mantle above only on the living room side, and about a 1ft deep "footing" only on the living room side. Both are at the same height, and otherwise symmetrical.

Any suggestions/advice greatly appreciated. Thanks
 
Also note: the bottom of the fireplace (like what you'd set your wood on inside) sits around a foot off the floor level. All stone on the outside, and a light colored brick on the inside, and an air space in between.
 
Took some measurements after getting home today, and my memory was a bit off. The flu is actually 15"x15", with only a minor offset halfway up (a couple/few inches over several feet), and from the top of the chimney to the bottom of the fireplace burn area is 20ft. More than enough room for 2 liners if I chose that route.

Here's a slightly related question: is there a wood-burning fireplace in existence that doesn't require a blower to heat well? I know it doesn't make much sense, since the stove would not be free-standing and able to have air move freely around it... but figured I'd ask the guru's of the subject.
 
Here's a slightly related question: is there a wood-burning fireplace in existence that doesn't require a blower to heat well?
In general wood burning fireplaces don't heat well at all regardless of blowers. The only exception is the built in wood stoves commonly referred to as high efficiency zero clearance fireplaces. But they are really stoves that are made to be built into a wall and they really do need a blower to heat to the best of their abilities
 
Took some measurements after getting home today, and my memory was a bit off. The flu is actually 15"x15", with only a minor offset halfway up (a couple/few inches over several feet), and from the top of the chimney to the bottom of the fireplace burn area is 20ft. More than enough room for 2 liners if I chose that route.
Yes if it is a 15" x 15" you will have plenty of room for 2 insulated liners.
 
Just took a couple photos, let's see if they attach.
Kitchen side:
[Hearth.com] Routing a cookstove to a fireplace chimney

Living room side:
[Hearth.com] Routing a cookstove to a fireplace chimney

The vents do not put out any heat when using the fireplace. They are connected to some older force air ducting that is no longer hooked up. The distance between the 2 opposing glass doors is about 4.5ft, and height off the main floor to the top of the glass door opening is about 39". It'll be close to try and get a rear vent made for the stove and not have it go down. I'm certain it'll be possible.
 
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Nice - So if I'm understanding this correctly you are going to drill a crock into the side of the fireplace and run a 6" insulated liner down the chimney and connect with black pipe the wood burning cook stove. The your going to install an additional 6" insulated liner down the same masonry flue and install a wood burning insert in the existing fire place? If so, that will be awesome.
There are many different inserts to choose from, I would lean toward an insert that sticks out the fire place (keep in mind the hearth needs to be 18" extended from the door) to get more radiant heat (w/ out blower) but you may end up running a blower during the coldest part of the year in Maine (September thru August... "joke")
Also consider a block off plate for the bottom of the chimney
 
Nope, no drilling. I'm going to route it right into the opening of the fireplace. I'll have JUST enough room height-wise to do so. I was planning on a block-off plate at the bottom of the chimney, just above the fireplace area, where 2 insulated liners will pass thru (will need to make holes for them).
 
Nice, just make sure there's no initial vertical stove pipe minimum coming from the flue collar, some stoves say you need a minimum vertical riser of 36" others don't say anything, you don't want the cook stove to fight you with smoke or draft issues, that could screw with the internal temps and mess up your food.
 
How far a "horizontal" run from the cookstove to the fireplace opening? Is the stove gonna sit right next to the fireplace opening? My cookstove is about 35" to top of cooktop and 44" from floor to where stovepipe connects. Some people do run several feet of pipe from the stove horizontally to the rising pipe. Not always the best set-up. I assume that near-horizontal run from the stove will be out of the way of someone accidentally touching it.... Double-walled pipe will help, in any case.

But as a can-do sort of guy, I am not discouraging this, might work out. You might consider bricking or "stoning" in the side of the fireplace through which the stove pipe will enter. Make it much simpler and easier to manage draft, etc. That is, if you decide to keep the thing a fireplace and not install an insert stove.
 
I'm guessing it'll be about 2.5ft of horizontal run to the "T" to the vertical insulated liner. If I decide to keep the other side a fireplace, I'll cut out a steel plate to fit in the opening of the fireplace where the stove pipe enters and seal it off to control draft around the liner.
 
Your setup is not actually that unusual. Dual-faced fireplaces were once common, in fact my family owned three separate houses that had them.

The normal method to add a cook stove in front of a fireplace is to thimble thru above the mantel. My 1770's house has thimbles above the mantel of both original cooking fireplaces.

The flue size is normal for a fireplace, if not a little small for dual openings. They do suck like a motha'.
 
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No, the stove needs a dedicated flue.
 
I thought the initial question included thoughts about two stoves on two separate 6" liners, one of which was a cookstove.
 
It was. I must have mistook your suggestion to mean have the cookstove on one side with a thimble, and still have an operable fireplace on the other, on the same flue.