Freestanding stove install venting through masonry fireplace.

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leco

New Member
Nov 29, 2016
27
KY
Hello hearth forum peeps. I have lurked around on and off for some time, gleaning some of the great info here. I am finally going to be able to get a stove going in the house, and just wanted to run my install by you all for a critique.

A buddy is moving out of his current place and selling me his Sierra 8000 TEC that he has been burning in a few seasons, for a friendly price. I have been gathering wood for a couple of years, so I have a few dried cords ready to go.

My house is ranch on a basement, with masonry chimney on the NNE facing wall. There is a fireplace both in the basement, and on the ground floor, each having a flue in the chimney. They basement flue is smaller, maybe 6x8, whereas the ground floor living room is terra cotta lined 13x13. This living room is in the corner of the "L" shaped house.

Here is a shot of the living room fireplace:
stove.jpg

The stove is too big to fit on the existing hearth, so my intention is to set it in the room, on a hearth pad I will build. The piece of cardboard in the photo represents the footprint of the stove, and is cut to that size (32x16.5) The stove has both a front and right hand side loading door.

The manual calls for 0.893 R in the pad, which I intend to build as a plywood base, 3 layers of Hardie board, and a slate tile top. Thinking it will end up 48"x60" to cover all the clearances.

The flue is about 14 feet from the top of the chimney down to the top of the fireplace opening. I intend to line this with an insulated stainless steel flex liner.

Now is where some questions come in. :) Standard seems to be to bring the liner down to a T, and then snout to your stove. My stove connector is going to sit about 48" from where the T would be. I am thinking that I will just angle the snout upward from the stove bit. I think I read somewhere that you want to get 1/4" of rise for every 12" of run, in the snout, but would like confirmation on this. I can actually get a bit more than that depending on how low I hang the T. Will having the snout angled affect how the snout connects to the T? Is it better to get a 48" snout, or just go with the standard, and extend it with stovepipe? Lastly, would it be better to just run flex, directly to the stove. Doing so would mean less horizontal pipe, but I think there are reasons to not go this route.

Thanks for looking. Feel free to ask any questions. I can provide some more pics if needed, or answer questions on measurements.
 
Now is where some questions come in. :) Standard seems to be to bring the liner down to a T, and then snout to your stove. My stove connector is going to sit about 48" from where the T would be. I am thinking that I will just angle the snout upward from the stove bit. I think I read somewhere that you want to get 1/4" of rise for every 12" of run, in the snout, but would like confirmation on this. I can actually get a bit more than that depending on how low I hang the T. Will having the snout angled affect how the snout connects to the T?
Yeah just angle it a little bit it will work fine.

Is it better to get a 48" snout, or just go with the standard, and extend it with stovepipe?
You are not going to get a 48" snout so you will have to extend it. Black pipe will work fine because it is exposed.

Lastly, would it be better to just run flex, directly to the stove. Doing so would mean less horizontal pipe, but I think there are reasons to not go this route.
Having the tee there will allow for some material to fall and build up in the tee cap without obstructing the pipe like it would if you did a slow sweep with the liner.
 
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Coming out of a stove with a 90 and then another 90 turn at the tee, connected to a short chimney doesn't sound like a good recipe for draft. Does the stove have an option to rear vent? If using single-wall connecting pipe it looks like the pipe or mantel will need shielding.
 
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Coming out of a stove with a 90 and then another 90 turn at the tee, connected to a short chimney doesn't sound like a good recipe for draft. Does the stove have an option to rear vent? If using single-wall connecting pipe it looks like the pipe or mantel will need shielding.
I missed that I thought it was a rear vent.
 
It may be an option. Haven't heard back from the OP yet.
 
Thanks for the replies.

Good to know on the catch can aspects of the T. That totally makes sense.

The stove does have a rear vent, that I intend to use.

I think it will be easier (and more attractive, to insulate the pipe going back to the T, rather than shield the mantel. What's the best way to do that? Insulate the horizontal pipe with the same insulation as the liner? Double wall pipe? Both? :)

Also, is there any concern with having only 14 vertical feet? Should I plan to extend with a pipe above the masonry?

Getting pretty excited over here. :)
 
I question why you are setting the stove so far out into the room Why do you not slide it back till it sits very close to the existing hearth?
 
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I question why you are setting the stove so far out into the room Why do you not slide it back till it sits very close to the existing hearth?

The manual calls for the following "MINIMUM CLEARANCE TO COMBUSTIBLES" for rear venting:
Unit to Side Wall - 18"
Unit to Back Wall - 26"
Flue to Side Wall - 31"
Flue to Back Wall - 18"

The distance placed is ~26" to the rear wall, aka, the hearth wall.

Am I interpreting these requirements incorrectly?
 
Well is the hearth wall combustible? You can also reduce those clearances by 2/3 by using some ventilated heat shields. I would push the stove all the way back against that existing hearth and shield anything as needed. But I doubt you would need to shield much. You can also put the shield on the stove if that would look better
 
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Well is the hearth wall combustible? You can also reduce those clearances by 2/3 by using some ventilated heat shields. I would push the stove all the way back against that existing hearth and shield anything as needed. But I doubt you would need to shield much. You can also put the shield on the stove if that would look better

So here is a couple better views of the hearth:
stove2.jpg
stove3.jpg

Bholler, when you say push the stove all the way back against the existing hearth, do you mean a) to still have setting on the wood floor, on a hearth pad, or b) setting on the brick that makes the hearth?

I am not sure I could do b) as there is only about 14" of depth there, and the stove is 16.5" deep. I'll check how the feet of the stove are laid out to see if that is even an option.

There is a lot of wood on the current mantle. I assume those wooden parts are considered combustible. I could remove that I suppose. I am also thinking that the stove will be more efficient out in the room. Am I off in thinking that?

...off to research shields here. :)
 
Bholler, when you say push the stove all the way back against the existing hearth, do you mean a) to still have setting on the wood floor, on a hearth pad, or b) setting on the brick that makes the hearth?
I mean a

There is a lot of wood on the current mantle. I assume those wooden parts are considered combustible. I could remove that I suppose. I am also thinking that the stove will be more efficient out in the room. Am I off in thinking that?
Then put a shield on the back of the stove. But really you would need to set the stove there and measre the distance between the stove and any combustible materials. I assume the mantle will be higher and wider than the stove so you will be measuing on a diagonal. You may make it. If not make up a sheet metal shield for the back of the stove with some 1" spacers.
 
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OK. Thanks for clarifying.

Then put a shield on the back of the stove. But really you would need to set the stove there and measre the distance between the stove and any combustible materials. I assume the mantle will be higher and wider than the stove so you will be measuing on a diagonal. You may make it. If not make up a sheet metal shield for the back of the stove with some 1" spacers.

Thanks again. I have been reading the site since my last post looking for details on shields. I've found a few nuggets and it seems that is the way to go. It would be nice to not give up so much of the room to the stove and pad, but a safe install is the primary concern.

Your post puts some more questions in my head.

Are distances to combustibles measured in a straight line? I.e. if my Unit to back wall clearance is 26", I would measure from the top rear of the stove, straight to the mantle, yes? What about the brick on the hearth wall? is that considered a combustible?

If I attach a shield to the back of the stove, that reduces the clearances to 1/3 of their previous value, yes?

How does this affect clearances from the stovepipe? How do I determine if I need to double wall or shield?

Thanks for the input on this. It's definitely helping my comfort level.
I'll be able to get some detailed measurements on the stove, at my buddy's place this weekend.
 
I took a look at the opening and where the stove would go if it were pushed back closer to the hearth as beholler suggested. Having looked at that, it looks like the best option is to make a shield from plate steel (or similar) and attach it to the lintel in the firebox. It would come out of the box horizontal, and then once clearing the masonry, angle up about 30 degrees.

By my estimation, this will solve all combustible clearance issues, from both the stove, as well as the stovepipe.

Can I attach directly to the lintel in the firebox, or do I still need ceramic spacers?
 
Can I attach directly to the lintel in the firebox, or do I still need ceramic spacers?
The lintel is non combustible so no need for spacers there.
 
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First I agree with everything bholler said. He is the pro here.

My next question though is why not pull off the rear legs and slide the stove in as far as you can? Unless you need a table, the farther you scoot it back the better.
 
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First I agree with everything holler said. He is the pro here.

My next question though is why not pull off the rear legs and slide the stove in as far as you can? Unless you need a table, the farther you scoot it back the better.

I like the idea, but not sure I can. I will know for sure this weekend, but I think the stove has a front and rear "leg" that runs the width of the stove. Not sure it is removable, but I will find out.

If I can, I'll need to platform my hearth pad, to ensure everything ends up level. Not a problem, but more gears turning. ;-)
 
I agree, make sure it can fit. But if it does, every inch it is out of your way the better.
 
Have you considered extending the hearth to make it fit on there?
 
Have you considered extending the hearth to make it fit on there?
I was just going to say this.

I'm not sure you're concerned about looks, but I would extend the hearth forward and then reface with a nice veneer stone/tile so it all blends together. Or do brick and repaint to match.
 
So, I have been at work on getting things sorted for this stove. While extending the existing hearth may be something I consider in the future, with an eye to kind of redo the entire look of the facade, it's not viable currently. Maybe in the next year or two.

I went ahead with my option of building a health extension, while pushing the stove back as far as possible. The legs on the stove are plate steel that run front to back, with some material between them. There seems to be a heat dispersion function built into it. Anyways, cutting legs did not appear to be a viable option either.

Here is a pic of the stove, after some wirebrush rust removal, and some painting with stove paint:

stove4.jpg

The plate that covers the top opening will be replaced. The stove will be vented out the back. I will get some better pics of the stove for yall soon.

Here is the hearthpad I built for it:

stove5.jpg

Tile on top of 3 sheets of 1/2" Durock, on top of a wood base/platform. Total R value of 1.19, exceeding the stoves pad requirement of 0.893 R value.

I will get that guy grouted and in place. Full length 6" liner, & insulation on order from a forum advertiser. Depending on how weather cooperates, could be burning by this weekend, but definitely by the end of the year. :)

I have a followup question on heat shields. If I intend to make a plate metal heat shield that bolts to the lintel, what size (thickness) steel do I need to use?
 
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Got my hearth pad completed; liner installed; makeshift heat shield built and installed; stove moved and connected. Ready for the first burn in this house! :)

20161212_203132~01.jpg 20161212_203220.jpg 20161212_203237.jpg
 
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First fire! :cool:

20161213_214351~01.jpg

Was getting about 600-700° on top. About 250-300° on the last uninsulated point of the chimney.
 
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