Installing a stove thru damper, sub-par heatalator fireplace

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Brianstrange

New Member
Dec 13, 2022
11
Ma
I acquired a VC Vigilant wood stove in great condition. The fireplace it's going in is an old heatalator kit showing signs of rust, enough for me to have little faith in it. I removed a smaller parlor stove that had a 6" pipe going thru a rigid insulation type material and the pipe vented into the damper opening in the center of the fireplace. That concerned me should there be a hidden failure point. The Class I flue that serves this fireplace is offset to the right by about 10". Because this is a heatalator, I would feel safer to run the stove pipe past the smoke shelf and directly into the 13x13 flue. Due to the size and heights I'm dealing with, it would be much easier for me to use a flex product allowing some movement to move the stove out and sweep the flue yearly. The offset and the room available is limiting. No matter how this is installed, the stove would need to be removed for cleaning as there would be no room to access a cleanout. I hope I've been descriptive enough. I also thought about installing a full liner but it's just not in the budget right now. The existing flue is in great shape and no cracks. I'd like to hear any suggestions that may apply in a case like mine. The stove will be used as an open burn fireplace (more practical than rebuilding the firebox) and occasional backup \ augmenting heat source 16-20 evenings per year.
 
I acquired a VC Vigilant wood stove in great condition. The fireplace it's going in is an old heatalator kit showing signs of rust, enough for me to have little faith in it. I removed a smaller parlor stove that had a 6" pipe going thru a rigid insulation type material and the pipe vented into the damper opening in the center of the fireplace. That concerned me should there be a hidden failure point. The Class I flue that serves this fireplace is offset to the right by about 10". Because this is a heatalator, I would feel safer to run the stove pipe past the smoke shelf and directly into the 13x13 flue. Due to the size and heights I'm dealing with, it would be much easier for me to use a flex product allowing some movement to move the stove out and sweep the flue yearly. The offset and the room available is limiting. No matter how this is installed, the stove would need to be removed for cleaning as there would be no room to access a cleanout. I hope I've been descriptive enough. I also thought about installing a full liner but it's just not in the budget right now. The existing flue is in great shape and no cracks. I'd like to hear any suggestions that may apply in a case like mine. The stove will be used as an open burn fireplace (more practical than rebuilding the firebox) and occasional backup \ augmenting heat source 16-20 evenings per year.
Your liner needs to run from the stove out the top of the chimney. Just dumping it out into a 12x12 is not an acceptable install and doesn't meet minimum safety standards
 
OP - no more direct connects per nfpa and insurance companies.
 
OP - no more direct connects per nfpa and insurance companies.
Actually that isn't technically accurate. A properly done direct connect is still allowed.

But the clay tile chimney needs to be code compliant (very few are).

It can't be more than I believe 3x the volume of the stove outlet (most fireplaces flues are definitely the 12x12 in question)

And you need to make a positive connection to that clay tile (which I have never heard anyone being able to figure out)

So in reality it really can't be done to code
 
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Actually that isn't technically accurate. A properly done direct connect is still allowed.

But the clay tile chimney needs to be code compliant (very few are).

It can't be more than I believe 3x the volume of the stove outlet (most fireplaces flues are definitely the 12x12 in question)

And you need to make a positive connection to that clay tile (which I have never heard anyone being able to figure out)

So in reality it really can't be done to code
Thank you. I do have clean access to the bottom of the tile, and could put a sealed pass thru on the underside. Even though this is the case, and the 12x12 is (barely) less than three times the volume, I'm learning that this could still lead to draft issues and is less desirable. In addition, I acquired the Vigilant for $150, and planned on mostly open fire use. It is a bit over-sized as a heat source for the basement level, and is better suited for our main living level. I'm starting to think that shifting to a smaller stove for the basement that offers the same operation (stove and open fire) might be a better plan, especially due to the investment in a liner.

With that as a possibility, would there be a significant difference between insulated flex and non insulated flex liner when the stove will normally be an open fire?
 
With that as a possibility, would there be a significant difference between insulated flex and non insulated flex liner when the stove will normally be an open fire
Absolutely a huge difference and most likely required by code
 
So I need to correct my original post. I described the the existing fireplace as a Heatilator which I'm seeing can also be a zero clearance type of fireplace as well (Third one below.) After looking at many pictures, I realize that my fireplace does have air chambers on either side, and the whole assembly is fitted inside a cinder block cavity. It's just a metal firebox with steel surround, shelf and damper, that exits into a masonry based hood feeding a 12x12 clay flue. The flue has an air gap around it, and is encased with cinder block on the basement level, transitioning to large red brick for another 1.5 stories. I'm reading lots of contradicting info out there about liners etc. I'm hoping this description helps for a better understanding of my existing conditions, but I plan to get some clearer photo's over Christmas break. In addition to the samples below, I'll look tonight if I have some of my fireplace tonight.

So this first pic appears to be close to what I have. A steel enclosure with a hood and a long cast damper (about 5 x 14" trapezoid shape):
[Hearth.com] Installing a stove thru damper, sub-par heatalator fireplace


It looks like this but fieldstone face - note, it burns wood:
[Hearth.com] Installing a stove thru damper, sub-par heatalator fireplace


It is NOT this style!
[Hearth.com] Installing a stove thru damper, sub-par heatalator fireplace
 
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So I need to correct my original post. I described the the existing fireplace as a Heatilator which I'm seeing can also be a zero clearance type of fireplace as well. After looking at many pictures, I realize that my fireplace does have air chambers on either side, and the whole assembly is fitted inside a cinder block cavity. It's just a metal firebox with steel surround, shelf and damper, that exits into a masonry based hood feeding a 12x12 clay flue. The flue has an air gap around it, and is encased with cinder block on the basement level, transitioning to large red brick for another 1.5 stories. I'm reading lots of contradicting info out there about liners etc. I'm hoping this description helps for a better understanding of my existing conditions, but I plan to get some good photo's over Christmas break. If I have photos at home, I'll post those tonight.
I assumed that and yes you still need a full insulated liner
 
Here are the interior photos of the steel liner\heatilator. If anyone knows the brand or model, please let me know. The first pic is the LR corner of the smoke shelf that is clearly littered with creosote. The second pic is looking up. I circled the edge of the smoke shelf, the warped area is the front. In order to run the 8" pipe to to the flue, I will have to cut into the smoke shelf. Am I right to say that the back angled panel that meets the front edge of the smoke shelf is a double wall cavity? Does that area connect to the side chamber vents on the face of the fireplace? I would like to keep the metal as in tact as possible, but realize it may not be possible. Also, I understand that a 8" pipe can enter a 12x12 ID clay liner. I'm also seeing "Bottom Plates" for a flue. Why would it not be an option to run insulated pipe to a bottom plate, and then use the clay the rest of the way?
[Hearth.com] Installing a stove thru damper, sub-par heatalator fireplace
[Hearth.com] Installing a stove thru damper, sub-par heatalator fireplace
 
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Here are the interior photos of the steel liner\heatilator. If anyone knows the brand or model, please let me know. The first pic is the LR corner of the smoke shelf that is clearly littered with creosote. The second pic is looking up. I circled the edge of the smoke shelf, the warped area is the front. In order to run the 8" pipe to to the flue, I will have to cut into the smoke shelf. Am I right to say that the back angled panel that meets the front edge of the smoke shelf is a double wall cavity? Does that area connect to the side chamber vents on the face of the fireplace? I would like to keep the metal as in tact as possible, but realize it may not be possible. Also, I understand that a 8" pipe can enter a 12x12 ID clay liner. I'm also seeing "Bottom Plates" for a flue. Why would it not be an option to run insulated pipe to a bottom plate, and then use the clay the rest of the way?
View attachment 305629View attachment 305630
You need a full insulated liner from top to bottom and cut out whatever you need to get the liner through
 
Yes, you mentioned it before. I'm attempting to learn why.
Because dumping an 8" stove into a 12x12 isn't going to work well or meet code. Your chimney currently meet code. There is no good way to attach to the bottom of the clay etc etc.
 
You’re describing a direct connect install - short piece of chimney liner terminated at the bottom 1/3rd of the chimney, no good.
Full liner from chimney cap to stove collar is needed, keeps flue gases warmer, keeps the crud that forms in the liner from falling down on top of your stove, adds to stove performance and is much safer incase you have a chimney fire
 
Because dumping an 8" stove into a 12x12 isn't going to work well or meet code. Your chimney currently meet code. There is no good way to attach to the bottom of the clay etc etc.
Actually that isn't technically accurate. A properly done direct connect is still allowed.

But the clay tile chimney needs to be code compliant (very few are).

It can't be more than I believe 3x the volume of the stove outlet (most fireplaces flues are definitely the 12x12 in question)

And you need to make a positive connection to that clay tile (which I have never heard anyone being able to figure out)

So in reality it really can't be done to code
Your previous comments are what have me curious. A 12x12 has a volume of 144. The 8" has a volume of 50.24 which is more than 33.3%. (On the edge, I get it....but within spec) Also "And you need to make a positive connection to that clay tile (which I have never heard anyone being able to figure out)" ..........I assume you mean the clay terminates to a 8" fitting (Possibly a sump as they refer to them in the UK?)
So with those statements, I'm trying also to understand why it can't be done, that's all.
 
You’re describing a direct connect install - short piece of chimney liner terminated at the bottom 1/3rd of the chimney, no good.
Full liner from chimney cap to stove collar is needed, keeps flue gases warmer, keeps the crud that forms in the liner from falling down on top of your stove, adds to stove performance and is much safer incase you have a chimney fire
Yes, that's how the existing stove is, but the pipe just goes into the throat. When the stove was made the instructions have the pipe loose in the clay pulling cool air with it.
 
From what I’ve seen (no where near as much as Ben) is people use to build a metal plate, install it in the chimney and cut a hole to size for the round pipe to go throw. Horrible to clean, and if you ever have a creosote fire, your making a huge mess putting it out (I’m a firefighter)
I one piece liner is the way to go
 
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Your previous comments are what have me curious. A 12x12 has a volume of 144. The 8" has a volume of 50.24 which is more than 33.3%. (On the edge, I get it....but within spec) Also "And you need to make a positive connection to that clay tile (which I have never heard anyone being able to figure out)" ..........I assume you mean the clay terminates to a 8" fitting (Possibly a sump as they refer to them in the UK?)
So with those statements, I'm trying also to understand why it can't be done, that's all.
Ok so maybe by the numbers the volume works for code. But the stove isn't going to work properly and the setup isn't going to be serviceable. Do you have the required clearances from the outside of the chimney structure to combustible materials?
 
Ok so maybe by the numbers the volume works for code. But the stove isn't going to work properly and the setup isn't going to be serviceable. Do you have the required clearances from the outside of the chimney structure to combustible materials?
It's an exterior brick chimney with clay flue on a block jog out. There is a gap between the exterior wall and the masonry, I will have to measure that next week, I recall that it was about 1.5". It's a timber frame home so the structure and the chimney are independent. In fact, the whole heatilator sits in masonry. If they only spent another $500 in 1975......... The purpose of this is for open fires, we do not heat with wood. I will say it's likely a one in 5 year ice storm event happens and if we're there we may be tempted to use it, but don't need to. We heat with heat pumps and have millivolt direct vent propane as our backup heat source.
 
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