Help with installing stove or insert into masonry fireplace with heatilator.

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Radude

New Member
Feb 9, 2020
22
Pennsylvania
Hi I'm completely new to this forum, fireplaces, stoves and inserts. I purchased a 1700sq ft house ( about 1200 sq ft is on the same floor as the fireplace and the rest is upstairs ) 2.5 years ago. I'm assuming I'd want something that will heat up to 1800 sq ft or so. My main heat source is an oil furnace. There's an unused fireplace in the living room that was put in around the 60s or 70s. The fireplace is missing the damper. It's been sealed off since we moved in to help reduce heating cost. After a fair amount of research I've decided I would rather use the area for a wood stove or insert because they're much more efficient and having a heat and cooking source that doesn't depend on electricity would be awesome. Upon initial inspection I found what I believe is a heatilator. I have a hearth that's 16" and 12" off of the floor. The fireplace opening is 36"L x 28"H x 16"D on the top and 22.5"D on the bottom. The back is 27"W for the first 14 inches from the bottom then begins to taper up and toward the opening to 31"W. If you're familiar with heatilators I hope these dimensions help, I did my best to describe it . I will include a few pictures to help visualize. The damper hole is 9W x 27 tapering to 15W. There's what I believe is the smoke shelf above the damper? The flue is Terra cotta lined with an ID of 6 5/8 x 11 3/8. I'm guessing I'll have to ovalize a flex liner to get it inserted? I was originally looking at a medium sized stove with a height of 28" but after some thought it seems it'll be some trouble getting the flue liner attached and overall just be a tight fit. I also haven't found any other stoves under 28" that are the size I'd prefer. Can I install an insert while keeping the heatilator intact or do I need to rip it out? Can they be cut out in sections? Will the brick behind the heatilator need to be protected by fire brick if it's exposed? Should the vents be closed or doesn't it matter? Can I cook in an insert? I haven't been able to find a model number for the heatilator. I'm sure I'm not the only one that has dealt with a situation like this and I'd like to hear everyone's thoughts. I'm on somewhat of a budget. I'd rather not go above $2,000 or so but I will go up to $3,000 if need be. I'm in the natural gas industry and my dad and I are pretty handy guys and catch on fairly quick when it comes to learning something new. We do just about everything ourselves. Any help would be much appreciated! I'd love to start using this fireplace again, just not in its current condition. I'm also looking forward to lower oil bills in the future! . Thanks in advance to everyone and anyone that can help with this!
[Hearth.com] Help with installing stove or insert into masonry fireplace with heatilator.[Hearth.com] Help with installing stove or insert into masonry fireplace with heatilator.[Hearth.com] Help with installing stove or insert into masonry fireplace with heatilator.[Hearth.com] Help with installing stove or insert into masonry fireplace with heatilator.
 
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I have the exact same job with what I believe an identical unit waiting for me. Can I co-sponsor your thread?
I will be closely watching this.
 
Yeah you will need an ovalized liner or to break out the old clay. I would recommend an oval liner. You may be able to get that oval through the damper. Or you may need to cut out part of the box. I can't really tell without being there.
 
I have the exact same job with what I believe an identical unit waiting for me. Can I co-sponsor your thread?
I will be closely watching this.

Absolutely! Do I have to add you as a sponsor somehow or is it something you do on your end? I'm not familiar with this thread at all yet.
 
Yeah you will need an ovalized liner or to break out the old clay. I would recommend an oval liner. You may be able to get that oval through the damper. Or you may need to cut out part of the box. I can't really tell without being there.

So it is feasible to cut sections of the heatilator out as necessary?
 
Yeah I do it all the time

Awesome, I'm glad to hear it's not out of the question. Do you face the newly exposed masonry with any fire brick or is it fine as long as it's outside of any clearances? I'm guessing it would be fine but I just want to make sure. The less I have to open it up in the future, the better. Is cleaning going to be an issue with the bends going around the damper / smoke shelf or will it be fine to pull a brush through?
 
Also, is the square footage rating I've been looking at adequate or should I go smaller ( forget the second floor ) or larger so I'm not pushing it too much. The ceilings on the first floor are about 9ft high or so.
 
Welcome to the Forums!!

My heatalator works fine with the insert. The vents still work, and throw heat.

Relined the chimney, cut the lintl to size, and 10 y years later, we're still cruising.

[Hearth.com] Help with installing stove or insert into masonry fireplace with heatilator.
 
Absolutely! Do I have to add you as a sponsor somehow or is it something you do on your end? I'm not familiar with this thread at all yet.
It's just a ceremonial, or honorary, or "in spirit" type of thing. Nothing to do on either end. Just means I am facing the same exact job and will be following this. Hope things go smoothly! Post your progress!
 
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My project was different, I busted out the clay liner and added a 6" insulated liner to my 30' chimney in November. Running an insert rather than a free stander, but that's a different issue.

One thing I will say while you are doing your planning and due diligence is to secure wood now. Get yourself one or two cords of wood and get it stacked and covered. The longer you season it, the happier you will be. I sourced 4 cords a year prior to my install, giving the hard maple one and a half summers to season. Checked it yesterday and am at 18%. Burning wet wood sucks. Most folks think about the wood after the install. Get ahead of the game --- you will not regret it.
 
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Hi I'm completely new to this forum, fireplaces, stoves and inserts. I purchased a 1700sq ft house ( about 1200 sq ft is on the same floor as the fireplace and the rest is upstairs ) 2.5 years ago. I'm assuming I'd want something that will heat up to 1800 sq ft or so. My main heat source is an oil furnace. There's an unused fireplace in the living room that was put in around the 60s or 70s. The fireplace is missing the damper. It's been sealed off since we moved in to help reduce heating cost. After a fair amount of research I've decided I would rather use the area for a wood stove or insert because they're much more efficient and having a heat and cooking source that doesn't depend on electricity would be awesome. Upon initial inspection I found what I believe is a heatilator. I have a hearth that's 16" and 12" off of the floor. The fireplace opening is 36"L x 28"H x 16"D on the top and 22.5"D on the bottom. The back is 27"W for the first 14 inches from the bottom then begins to taper up and toward the opening to 31"W. If you're familiar with heatilators I hope these dimensions help, I did my best to describe it . I will include a few pictures to help visualize. The damper hole is 9W x 27 tapering to 15W. There's what I believe is the smoke shelf above the damper? The flue is Terra cotta lined with an ID of 6 5/8 x 11 3/8. I'm guessing I'll have to ovalize a flex liner to get it inserted? I was originally looking at a medium sized stove with a height of 28" but after some thought it seems it'll be some trouble getting the flue liner attached and overall just be a tight fit. I also haven't found any other stoves under 28" that are the size I'd prefer. Can I install an insert while keeping the heatilator intact or do I need to rip it out? Can they be cut out in sections? Will the brick behind the heatilator need to be protected by fire brick if it's exposed? Should the vents be closed or doesn't it matter? Can I cook in an insert? I haven't been able to find a model number for the heatilator. I'm sure I'm not the only one that has dealt with a situation like this and I'd like to hear everyone's thoughts. I'm on somewhat of a budget. I'd rather not go above $2,000 or so but I will go up to $3,000 if need be. I'm in the natural gas industry and my dad and I are pretty handy guys and catch on fairly quick when it comes to learning something new. We do just about everything ourselves. Any help would be much appreciated! I'd love to start using this fireplace again, just not in its current condition. I'm also looking forward to lower oil bills in the future! . Thanks in advance to everyone and anyone that can help with this!View attachment 256765View attachment 256766View attachment 256767View attachment 256768
I had a similar heatilator setup that I installed an insert into. You will need to notch the damper opening to get the liner to fit. You will need to fabricate a block off plate that will go above insert below the damper. Insulating or buying an insulated liner is the best option. Do it once and do it right. I stuffed my smoke shelf area, heatilator vents , and glued a layer of roxul to the non stove side of my block off plate. I had a buddy fabricate some metal plugs for my vents so no critters crawled out. If you start cutting the back metal wall of the insert there is an insulation behind it either rock wool (spelling?) Or asbestos . So i would not recommend it.Try to get an insert that extends into the living space as it helps with heat transfer. Depending on your hearth clearances. I used cardboard templates to check my clearances ten times before ordering my insert. The back wall as it tapers in as you gain height is a pain to measure and account for. Search my other posts or the many ones on block off plates it will make a big difference. Good luck .
 
I have a 1939 Heatilator fireplace, and I had a BK Sirocco 25 installed in it. I had a CSIA certified chimney sweep install it, and he had to cut out the steel top of the fireplace in order to get the new steel liner down the chimney. It was apparently a very time consuming job, as that steel in that old Heatilator is very thick.

My stove dealer gave me a measurement sheet to fill out, and the Sirocco was the only one that would fit. I really wanted the Princess, but I am very happy with my Sirocco.

My little house is about 1300 square feet, and the fireplace is in the living room on the main floor, above the hot air furnace in the basement. Here in Newport we burn fuel oil, and my furnace is 20 years old so I have to replace that big daddy this summer, but it does keep the house relatively warm when I don't have a fire going. (I have yet to restore my original double hung windows.)

Just opposite the fireplace are the open stairs to the second floor, and the fan on the Sirocco does very well in pushing the hot air upstairs. The chimney goes through the master bedroom, but the BK really does keep my little house toasty, even in the upstairs rooms on the opposite side of the stairs.
 

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I had a similar heatilator setup that I installed an insert into. You will need to notch the damper opening to get the liner to fit. You will need to fabricate a block off plate that will go above insert below the damper. Insulating or buying an insulated liner is the best option. Do it once and do it right. I stuffed my smoke shelf area, heatilator vents , and glued a layer of roxul to the non stove side of my block off plate. I had a buddy fabricate some metal plugs for my vents so no critters crawled out. If you start cutting the back metal wall of the insert there is an insulation behind it either rock wool (spelling?) Or asbestos . So i would not recommend it.Try to get an insert that extends into the living space as it helps with heat transfer. Depending on your hearth clearances. I used cardboard templates to check my clearances ten times before ordering my insert. The back wall as it tapers in as you gain height is a pain to measure and account for. Search my other posts or the many ones on block off plates it will make a big difference. Good luck .

After measuring everything 50 times I decided to go with a Drolet 1800i. I got the trio package for less than 1500! I don't think I NEED to but I am going to cut a notch into the damper area as you said just for the sake of my flue being straighter. I planned on insulating with perlite due to the really tight fit I would have by wrapping the liner. I already have to ovalize a little and with the wrap I'd have to ovalize even more. I was going to fabricate a block off plate with some to k wool to fit right where the damper was and create a plug for the perlite. You suggest bringing it down further? I'm excited as hell! I'd never would have thought I'd excited over a piece of steel that can burn wood . The Drolet is going to come out onto the hearth more than I had originally anticipated. After more research I found that since my hearth is raised I could go with a hearth extension to get my the front clearance. Thanks for your input! It's much appreciated and I will definitely be looking up your posts for that block off plate. I may have already read them. I've been through more than a few already .
 
It's just a ceremonial, or honorary, or "in spirit" type of thing. Nothing to do on either end. Just means I am facing the same exact job and will be following this. Hope things go smoothly! Post your progress!

Yes I will definitely try to stop and take some pictures to help any others who decide to go down this path. It was a bit of a pain at first but it should all be worth it in the end!
 
My project was different, I busted out the clay liner and added a 6" insulated liner to my 30' chimney in November. Running an insert rather than a free stander, but that's a different issue.

One thing I will say while you are doing your planning and due diligence is to secure wood now. Get yourself one or two cords of wood and get it stacked and covered. The longer you season it, the happier you will be. I sourced 4 cords a year prior to my install, giving the hard maple one and a half summers to season. Checked it yesterday and am at 18%. Burning wet wood sucks. Most folks think about the wood after the install. Get ahead of the game --- you will not regret it.
 
I have a fair amount of wood in the yard that I've been collecting for our fire pit. I typically grab it when I can from work or elsewhere. I'm playing on buying some of those ecobricks / bioblocks and give them a shot. I've heard good things about them. Have you tried them?
 
After measuring everything 50 times I decided to go with a Drolet 1800i. I got the trio package for less than 1500! I don't think I NEED to but I am going to cut a notch into the damper area as you said just for the sake of my flue being straighter. I planned on insulating with perlite due to the really tight fit I would have by wrapping the liner. I already have to ovalize a little and with the wrap I'd have to ovalize even more. I was going to fabricate a block off plate with some to k wool to fit right where the damper was and create a plug for the perlite. You suggest bringing it down further? I'm excited as hell! I'd never would have thought I'd excited over a piece of steel that can burn wood . The Drolet is going to come out onto the hearth more than I had originally anticipated. After more research I found that since my hearth is raised I could go with a hearth extension to get my the front clearance. Thanks for your input! It's much appreciated and I will definitely be looking up your posts for that block off plate. I may have already read them. I've been through more than a few already .

That is a great price! Message me where you found that if you are willing.
 
After measuring everything 50 times I decided to go with a Drolet 1800i. I got the trio package for less than 1500! I don't think I NEED to but I am going to cut a notch into the damper area as you said just for the sake of my flue being straighter. I planned on insulating with perlite due to the really tight fit I would have by wrapping the liner. I already have to ovalize a little and with the wrap I'd have to ovalize even more. I was going to fabricate a block off plate with some to k wool to fit right where the damper was and create a plug for the perlite. You suggest bringing it down further? I'm excited as hell! I'd never would have thought I'd excited over a piece of steel that can burn wood . The Drolet is going to come out onto the hearth more than I had originally anticipated. After more research I found that since my hearth is raised I could go with a hearth extension to get my the front clearance. Thanks for your input! It's much appreciated and I will definitely be looking up your posts for that block off plate. I may have already read them. I've been through more than a few already .
Do you have the required clearance from the outside of the chimney structure to any combustible materials? If not which most don't you need to insulate properly for code compliance and safety. With pour in that means you need atleast 1" of insulation surrounding that liner. Which means you need more space fore pour in insulation. And again don't use loose fill perlite or vermiculite you will regret it later if you do.
 
I spoke to a tech from Drolet earlier today and he suggested going with pour in instead of the wrap due to how much more id have to ovalize to account for the extra 1"+ of diameter it will add. So you're saying it needs to be wrapped with insulation prior to being insulated with any loose material? The inside dimensions of my current clay liner is 11 3/8 " x 6 5/8". I'm not extremely worried about cost but I also don't want to fight with it too much while trying to insert.
 
I mean, technically it doesn't need to be insulated, correct? I just figured it was good measure to reduce cresote buildup and increase efficiency.
 
I mean, technically it doesn't need to be insulated, correct? I just figured it was good measure to reduce cresote buildup and increase efficiency.
It probably does need to be insulated yes. That is why I asked if you had the required clearance to combustibles.

And no you don't have to wrap the liner before you pour insulation but to use pour in insulation you need at minimum an extra 2" of space so you can have 1" on all sides. If you are ovalizing you will probably have to go up to a 7" liner to maintain proper volume.
 
Well let me start off by saying thanks for bringing it to my attention that missed something! I haven't seen any literature regarding clearance to combustibles when inserting through an existing masonry flue. Guess my ADD kicked in at that point. I seen the clearances for the roof part and that's covered. I just did more reading and it seems it's better to stay round all around xD. Sooo, it seems I'm going to be knocking some clay out, huh? I thought for sure I had everything covered. I feel like an idiot now haha.