Venting a wood stove through a prefab/zero clearance fireplace?

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1Dtml

Feeling the Heat
Nov 22, 2011
306
CT
Is venting a wood stove through a prefab/zero clearance fireplace safe, legal, or even a good idea?

I have a Heatilator E36 zero clearance fireplace, and I would like to install a wood burning stove by sleeving the 8" chimney and installing a new cap.

I have also read that using a pellet burning stove might be a better idea, but I prefer a wood burning stove, so any comparisons on these two options are welcome.

I have tended wood burning stoves before, but I am a newbie to pellet stoves.

I have also looked into inserts, but this makes me even more nervous than the other two options, and would not give me enough heat output to be worth the effort due to the size of my zero clearance fireplace.

Thank you for your help and ideas.

1D
 
In order to safely use the existing vent, you will have to run an
insulation-wrapped liner down thru the existing fire place venting
to a tee, then a horizontal connector pipe to your stove.
You will also have to make sure you meet the clearances to combustibles
to the rear of the stove & above the connector pipe...
It's not a perfect install but it will work. You should talk to your local
code enforcer to make sure HE will sign off on it.
 
1Dtml said:
Is venting a wood stove through a prefab/zero clearance fireplace safe, legal, or even a good idea?

I have a Heatilator E36 zero clearance fireplace, and I would like to install a wood burning stove by sleeving the 8" chimney and installing a new cap.

I have also read that using a pellet burning stove might be a better idea, but I prefer a wood burning stove, so any comparisons on these two options are welcome.

I have tended wood burning stoves before, but I am a newbie to pellet stoves.

I have also looked into inserts, but this makes me even more nervous than the other two options, and would not give me enough heat output to be worth the effort due to the size of my zero clearance fireplace.

Thank you for your help and ideas.

1D

I took on the same project a few years ago. I had a superior fireplace insert venting into a double wall galvanized flue that was inside a wood/vinyl sided chase. I came to the conclusion that a insulated liner inside the existing flue wouldn't be up to code. I elected to tear out the existing metal flue and replace it with a 2100HT Class A chimney system, making sure the exterior of the new pipe was never more than 2" away from combustibles. The pipe wasn't cheap but It was fairly easy to install.

DSC00530.jpg

DSC00572.jpg
 
I have the E36 also in the main living area. I explored the same option as you. Your Heatilator uses an 8" air insulated pipe. Its built just like a Class A but without the insulation in between the inner and outer pipe to give it the 2000 degree rating. Your chimney pipe has a pretty good rating already. So if you lined it IMO it would have to be way safer than a stand alone Class A and what could be safer than the stove transition being inside the firebox. I can't see where there could possibly be a clearance to combustibles issue there like some warn off. You have a 36" fire box with ceramic brick over top of steel and then there are clearances outside of that. My god how much clearance do people want. Unless its in the middle of a room I've never seen a free standing near the wall install have more fire block or clearance than a pipe coming out of the E36.
Maybe next yr we will ad a stove to the first floor and block of the existing E36.
I first looked into inserts also but they are very expensive, few choices to fit that FP, and then I would most likely be listening to a blower. My chimney pipe off the E36 is run the same as if it were a Class A with plenty of clearance up the chase, fire blocked, and inside of chase is wrapped in fire blocking insulation. I see no reason to tear out that install when it can be lined.
 
I would like to get to the bottom of this because my chimney chase is inside a 35' stone covered chimney that is stone inside and out. So the simple tear out that some think it could be is not so for some of us. To do that would be throwing away 25K worth of chimney. Burning wood full time wasn't on my radar 17yrs ago or it would have had a class A put in then.
 
wkpoor said:
I would like to get to the bottom of this because my chimney chase is inside a 35' stone covered chimney that is stone inside and out. So the simple tear out that some think it could be is not so for some of us. To do that would be throwing away 25K worth of chimney. Burning wood full time wasn't on my radar 17yrs ago or it would have had a class A put in then.

I know I started this thread, so I feel for you because mine isn't as complex as 25K worth of chimney.

Myself I can't take the chance, especially if an insurance company has an excuse not to cover an accident, so I'm almost positive that a pellet burning stove can be sleeved legally and safely, and if not you can certainly vent it somewhere even if you drill right through the back of your prefab fireplace.

I hope this gives you another option.

Thanks to all for the advice and information,

1D
 
1Dtml said:
wkpoor said:
I would like to get to the bottom of this because my chimney chase is inside a 35' stone covered chimney that is stone inside and out. So the simple tear out that some think it could be is not so for some of us. To do that would be throwing away 25K worth of chimney. Burning wood full time wasn't on my radar 17yrs ago or it would have had a class A put in then.

I know I started this thread, so I feel for you because mine isn't as complex as 25K worth of chimney.

Myself I can't take the chance, especially if an insurance company has an excuse not to cover an accident, so I'm almost positive that a pellet burning stove can be sleeved legally and safely, and if not you can certainly vent it somewhere even if you drill right through the back of your prefab fireplace.

I hope this gives you another option.

Thanks to all for the advice and information,

1D

Start a thread in the Pellet Mill Forum. Ask the same question and for any advice. If your looking in the Pellet direction. I have 3 pellet stoves and a wood stove. Love both sides of the story for different reasons.

My 2 cents.
 
DexterDay said:
1Dtml said:
wkpoor said:
I would like to get to the bottom of this because my chimney chase is inside a 35' stone covered chimney that is stone inside and out. So the simple tear out that some think it could be is not so for some of us. To do that would be throwing away 25K worth of chimney. Burning wood full time wasn't on my radar 17yrs ago or it would have had a class A put in then.

I know I started this thread, so I feel for you because mine isn't as complex as 25K worth of chimney.

Myself I can't take the chance, especially if an insurance company has an excuse not to cover an accident, so I'm almost positive that a pellet burning stove can be sleeved legally and safely, and if not you can certainly vent it somewhere even if you drill right through the back of your prefab fireplace.

I hope this gives you another option.

Thanks to all for the advice and information,

1D

Start a thread in the Pellet Mill Forum. Ask the same question and for any advice. If your looking in the Pellet direction. I have 3 pellet stoves and a wood stove. Love both sides of the story for different reasons.

My 2 cents.

Soon after I realized that I had a 1700 degree pipe, and needed 2100 degree for a wood stove I posted the same question in the pellet forum, but I have not seen any response yet.

I have looked through many pellet stove installation guides, and these show the installation is legal, but I have yet to find out the temperature rating of Pellet stove vent?

But as I mentioned pellet stoves are most commonly direct vented with very little clearance issues, so a direct vent can be used on almost any install but location-location-location could be the only problem.
 
Gave you a little "bump" over there. The temp to a pellet vent wont get nowhere near 1,000*. Pellet stoves mostly require 500* RTV. Most temps, unless inside the firebox, are well under 500*.

If the manual states its o.k. for a Pre-fab and to use a liner, then thats all that matters. Meet the Manufacturers recommendations and the Venting requirements and your good to go.
 
DexterDay said:
Gave you a little "bump" over there. The temp to a pellet vent wont get nowhere near 1,000*. Pellet stoves mostly require 500* RTV. Most temps, unless inside the firebox, are well under 500*.

If the manual states its o.k. for a Pre-fab and to use a liner, then thats all that matters. Meet the Manufacturers recommendations and the Venting requirements and your good to go.

Thanks for the "bump" and I appreciate the information.

1D
 
Project update:
After meeting with the local inspector this project would entail removing the existing zero clearance fireplace and the existing chimney (not the wooden chase).

A new and approved chimney system (2100* class A) would need to be installed, provisions for all clearances would need to be followed, and a correct R-value hearth installed according to the wood stove manufactures specifications.

In the end just about anything can be done as long as it meets all code, and manufactures instructions, and regulations.

It all depends on how committed you are to the project, and of course staying on budget.

I hope this information is helpful to those with a similar project, and I sincerely thank all of you for all your help and information.

I'll try to answer any questions about this if needed, but please don't shoot the messenger, remember to do your own research, and then meet with your own local code inspector/enforcer for final approval.

1D
 
I elected to demo the entire ZC and go with an alcove:

Alcovefan001.jpg


I simply used a ceiling support box for the Class A chimney in the new ceiling of the alcove:

Alcovefan004.jpg


And ran the class A up through the existing chase where the ZC Vent was originally:

coal001-1.jpg


My particular stove sits just outside the alcove as I need more BTUs than alcove approved appliances provide.

In the summer the stove goes out and I put the bar in the alcove:

Alcovefan007.jpg
 
Very nice indeed! :coolsmile:

1D
 
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