Fireplace adapt

[mj5001]

First post and one of several questions--

If you can burn a fire in a fireplace then why can't you use a wood stove with one?

When I moved into the house, there was a complete fireplace insert (with a "stove" back) and it just had a port on the back that didn't tie to anything -- it just blew out it's smoke through the damper.

I plan on completely enclosing the front of my fireplace with steel (from the back for a perfect seal) and then running the stove duct through it toward the damper. The stove will stand in front of the fireplace -- not in it. And I imagine I should have "some" small fresh air holes in the bottom of the plate? Not many though?



The chimney will be cleaned and I'm hoping I'll be ok -- at least for this winter -- if I need to improve. I'll do it next year.

I want an EPA stove and this fireplace is fantastic, solid limestone and nothing but concrete everywhere -- no studs of any kind nearby.

I'll try to get "some" pipe up the chimney but the damper is a large rectangle -- don't know if it's possible and if it's a pain, I'm dropping it -- don't know why just a cover and the pipe going through it won't work.

If a fireplace fire can be pulled through a damper into the chimney, I don't know why stove smoke won't either?

 

[jatoxico]

Hi welcome the forum. I think the issue could be that any open fireplace uses much more air than new stoves. Of course all the air used is your already heated air from the house which is why you can't heat effectively w/ an open fireplace (as I can tell you from firsthand experience :shut: ). The large volume of air heated by the open fire requires a large flue to carry it out through the chimney.

When your install a newer stove that controls air fed to the fire, the volume of air going up the chimney is much less. That small volume fed into a large flue can result in poor draft and cold flue temps. Others here can prob explain better.

Might work but check the stove you get for flue requirements (most call for SS liner) and be careful. Better safe than sorry.

 

[begreen]

Welcome MJ5. What you are proposing, may work, but it may work poorly. Most modern stove have an 6" flue with an area of ~28 sq in. The throat of this chimney is likely a lot larger, say 10x12" or 120 sq in. In other words, over 4 times the cross sectional area. This will dramatically affect draft. Think of it this way - it's easy to drink with a straw, but a lot harder to drink with a 1" pipe. There are other confounding factors that will make this worse, like a cold exterior chimney and the stove will be rear exit, introducing a 90 deg turn in the smoke path. All this slows down the smoke and can lead to draft reversal and a very hard to start stove. The net result can be very unsatisfying with symptoms like balky starts, smoke spilling out whenever the stove doors open and worse, frequent puffbacks.

Your plan will work with a liner. Getting a properly sized stainless liner in there is not the end of the world. If you can supply some dimensions we can talk better about solutions. Can you provide:

1) a description of the chimney including height and throat size. Is it interior or exterior?
2) what is the width of the damper opening?
3) what is the height of the lintel at the opening of the fireplace?

PS: no vent holes will be required in the steel sheet covering the opening.

 

[mj5001]

The lintel height is 27" and the damper is about a 27" by 5 or 6" rectangle. Chimney is interior (close to center of house) and built like a tank -- proabably 3' or so limestone completely surrounds the chimney. the throat looks like that 10 x 12 dimension (2 flues -- other smaller one I imagine goes to basement for gas -- not using it though, have an electric tankless water heater.

If I do do this, the stoves I'm looking at vent through the top, so I would do one elbow -- then through the plate, then a straight shot? or should I do another elbow, pointing up?

This is a single story house, so chimney is maybe 3 or 4 feet higher than roof peak.

Do want an EPA stove -- I like the Drolet's -- but more on that in another post.

House is only 1700 sq feet and has a 2/3rds basement.

 

[mj5001]

By the way, you say a large chimney could create poor draw but does it actually effect the efficiency of the stove and btu output?

 

[begreen]

The problem with venting from the top is that the top of the horiz. section of pipe will be well over the height of the lintel. Smoke does not go downhill or at least not without very strong draft. This is why I asked. 27" is going to be a constraining factor because many stoves that have rear exit flues are above this height. For a top vented stove you will need to either punch a hole from the room side into the flue above the damper or perhaps it would be a lot easier to tap into that other flue if it's definitely unused.

 

[jatoxico]

The lintel height is 27" and the damper is about a 27" by 5 or 6" rectangle. Chimney is interior (close to center of house) and built like a tank -- proabably 3' or so limestone completely surrounds the chimney. the throat looks like that 10 x 12 dimension (2 flues -- other smaller one I imagine goes to basement for gas -- not using it though, have an electric tankless water heater.

If I do do this, the stoves I'm looking at vent through the top, so I would do one elbow -- then through the plate, then a straight shot? or should I do another elbow, pointing up?
This is a single story house, so chimney is maybe 3 or 4 feet higher than roof peak.

Do want an EPA stove -- I like the Drolet's -- but more on that in another post.

House is only 1700 sq feet and has a 2/3rds basement.

Assuming I am correctly envisioning what you want to do, for me to imagine your idea having any chance of success you should get that stack pointed in the right direction and up the chimney a ways. To dump the exhaust into the old firebox an expect it to effectively migrate up the chimney seems unlikely to me.

As far as BTU output, I believe draft effects the burn charectoristics of the entire stove including secondary burning.

 

[fossil]

You're re-inventing the term slammer. There isn't a stove manufacturer in the country that would endorse your plan, nor an insurance carrier that would cover your home in case of any sort of loss associated with an installation like that. Why? Because that configuration has never been tested or certified, and the basic reference for solid fuel-burning appliances, NFPA 211, has nothing resembling what you've described among the acceptable installation configurations. See the recent thread below for a somewhat similar discussion. Seems to me that it would actually be less bother to just do it correctly. You probably have a good candidate location there for a very nice hearth stove installation. A whole lot of folks a whole lot smarter about every aspect of wood burners than you or I have spent many decades developing and refining all the industry standards to make modern installations as safe and effective as we know how. I'm not about to go second-guessing that sort of knowledge bank and thinking that I can reinvent the wheel when the safety of my home is involved. Rick

https://www.hearth.com/econtent/index.php/forums/viewthread/81026/

 

[mj5001]

The lintel is actually much higher than the top of the stove, the bottom of the fireplace opening to the top of the lintel is 27" the bottom of the opening is 19" high from the floor. Floor to lintel is 43" (I just went to measure).

So the pipe would probably fall right in the middle (or really, wherever I want to be) of the steel cover.

The stoves I'm looking at have been around 28 to 30" high. There would be ample tile (on a concrete floor) as a base. (yes, concrete AND a basement below). So, begreen -- how's it looking now?

 

[mj5001]

I hope I made it clear also that the stove will be IN FRONT of the fireplace opening and like I say, below it. The back of the stove will be several inches from the cover plate -- or more if need be.

 

[North of 60]

I hope I made it clear also that the stove will be IN FRONT of the fireplace opening and like I say, below it. The back of the stove will be several inches from the cover plate -- or more if need be.

Go with a full SS liner top to bottom and attach it to your EPA approved stove of your choice and be done with it. The school of hard knocks already has had a class on this so why put yourself through it. An inspection will likely have to take place to receive full coverage on your insurance. Keep it simple. RUN A FULL LINER.
Cheers.

 

[begreen]

Got it. If I have this correct, you would be introducing 2 - 90's right off the stove + about a 4 ft. horiz run. Is that right? That sounds like a recipe for bad draft. Maybe look at some rear exit stoves for a better operation. And yes, you will definitely need a 6" liner, but so far I haven't heard of any serious obstacle for this to happen.

I'd recommend taking look at the Buck 261 stove as a starter.
http://www.buckstove.com/wood/model261.html

 

[DanCorcoran]

So your hearth is 19" high, and you'll put the stove on the floor in front of the hearth. You'll probably need some heat protection beneath the stove, but sounds like you'll have more flexibility with the flue. It'll still need to take a 90 degree turn into the fireplace (through the steel plate), then another to go up the chimney. Those two turns alone will significantly reduce draft. With 120 sq. inches of chimney instead of 28 sq. in., you'll be unlikely to get a decent draft. If you do this (without lining the chimney), just be prepared for the possibility of needing to line it later.

 

[DanCorcoran]

MJ5,
I may have missed this, but where are you? Alaska, Florida, or somewhere in between?

 

[sebring]

You are just like me. I had a large chimney without a liner. The guys at the forum convinced me to get a stainless steel liner installed. Ordered it online, installed it with a friend in under 2 hours. Now my stove doesnt smoke when I open the door to add wood, and I can shut the door tight and the draft is good enough to run on low air setting and get secondary burn. Worth every penny.

 

[mj5001]

I'm in the midwest -- so how do I get through the rectangular damper with the liner? Are there adapters?

It would be a hell of a job to bang through -- but I guess it could be done -- the damper itself is a very nice guage of steel.

 

[North of 60]

I'm in the midwest -- so how do I get through the rectangular damper with the liner? Are there adapters?

It would be a hell of a job to bang through -- but I guess it could be done -- the damper itself is a very nice gauge of steel.

Cutting torch, mini grinder with a cutting disc, sawzall. What is the size of the existing opening? Maybe a 5.5" liner will work.

 

[mj5001]

Ok -- 5 to 6" liners? That sounds easier then. What if I had to crimp it slightly as it fits into the damper? Is that ok?

Start from the roof I would guess.

And -- I would still use the steel cover toward the front of the fireplace (or I guess concrete board also works).

I'll search for liners, would appreciate some online sources and what to look at.

Is there a "flexible liner" available? Something you could pull on and it expands in length? Or is it just steel sections you fasten together?

I'll do this.

 

[mj5001]

Actuall I think getting a 5 or 6" opening wont be tough -- I can use my sawzall and a fresh blade -- the steel is pretty old and somewhat rusted because it didn't have a cap on the chimney when I moved in here.

 

[mj5001]

I wanted to ask something else --

Originally I was looking at this small Vogelzang defender epa stove.

It would actually fit IN the fireplace with room for some sort of blower behind it.

That would look so much nicer and it free up my floor space.

If you can blow the heat out to the room pretty well is it a real sacrifice to put the stove IN the fireplace?

Or do you juts lose to much heat?

Obviously, I would seal the top near the damper perfectly for no heat loss.

 

[mj5001]

actually, the Drolet is the stove I like -- the Eldorado. And it would actually fit IN the fireplace.

 

[jatoxico]

I wanted to ask something else --

Originally I was looking at this small Vogelzang defender epa stove.

It would actually fit IN the fireplace with room for some sort of blower behind it.

That would look so much nicer and it free up my floor space.

If you can blow the heat out to the room pretty well is it a real sacrifice to put the stove IN the fireplace?

Or do you juts lose to much heat?

Obviously, I would seal the top near the damper perfectly for no heat loss.

Lots of people install exactly as you describe, totally acceptable and you will get plenty of heat from the right sized stove. Didn't want to totally shoot down your previous idea but using a full liner and sealing off damper is the way to go. Liner can be "ovalized" if needed but removing some damper material so the liner can pass through is also very commonly done.
Now time to pick the right stove, married? :lol:

 

[begreen]

I'm in the midwest -- so how do I get through the rectangular damper with the liner? Are there adapters?

It would be a hell of a job to bang through -- but I guess it could be done -- the damper itself is a very nice guage of steel.

If you have 6" clear at the damper, no problem. with 5" clear the liner would need to be slightly ovalized at the damper to pass through. Many folks either cut a notch in the damper or remove it entirely. But you must put a sign on the back of the fireplace notifiying future owners of the house of its removal and that the fireplace is inoperable without it.

 

[mj5001]

Awesome -- I'm looking forward to getting setup. Yes, I'll put in the liner -- most of the stoves I'm interested in have a 6" outlet, so I stick with that? Or do I dare try the 5"? (Medium stove, single story house, well insulated). I t seems also, that all of them have top vents -- typical with epa stoves?

And I'm real happy that IF the stove fits IN the fireplace with a good blower behind it, that's acceptable.

I was concerned the fireplace itself would absorb a lot of heat and cut down on efficiency? But it is a small room and need as much floor space as possible.

One final question --

a good source for the liner?

I saw Build.com -- that looks pretty good, or maybe my local Menards?

 

[mhrischuk]

Could you post some pictures please?