Power Venting a wood stove?

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dgarver

Member
Dec 18, 2010
14
North East OH
Hello all,


My wife and I are set on purchasing a wood stove in the near future as supplemental heat for our 1600 sq/ft home. We are running into conflicting stories from local shops however. One shop told us we couldn't or at least shouldn't run our chimney out through our wall and up the side of the house. We have a two story home, and absolutely do not want to punch a hole through the roof. Another said it would be just fine. I am leery of installing the recommended chimney at all, since it is going to cost more than the stove will. So, this brings me to my question, is it possible to use a forced air venting system, like those used on a gas fired hot water heater for example, to push out the smoke from the wood burner? I have seen pellet stoves using this exact technology, so I wondered why it isn't used on wood stoves? Is it something for air supply or what? Can anyone elaborate on exactly where the air comes from that will feed the fan that is blowing out the chimney? What I mean is, our house is well sealed, and if the fan's intake side is open to our houses air, and is sending our house's air right out the vent, is that going to create an issue? Is that where the "direct vent" pipe comes in? Any helpful information would be appreciated. We are trying to find a reasonably priced way to vent the stove.


Thanks!
 
You're going to need a proper class A chimney to vent the stove.

Either out the wall and up the side of the house or straight up through the roof.
 
A solid fuel burning appliance will require a proper, UL listed Class A chimney or masonry chimney that is built up to code.
 
Nope. No power venting a wood stove. Having a full load of wood burning and having a power vent fail would be a disaster like you haven't seen. With oil, gas and pellet at least they can shut down. You can't yell "whoa" at a flaming load of wood and get any results.

And yes for the record Consumer Reports said in an article that you could use a power vent. They were wrong.
 
BrotherBart said:
Nope. No power venting a wood stove. Having a full load of wood burning and having a power vent fail would be a disaster like you haven't seen. With oil, gas and pellet at least they can shut down. You can't yell "whoa" at a flaming load of wood and get any results.

And yes for the record Consumer Reports said in an article that you could use a power vent. They were wrong.

Assuming the power never failed, would it work>? I have a battery backup system, I would be running a 12v fan on a trickle charger and marine battery.
 
Seriously, please do not do what you are thinking, it is unsafe and your insurance would never cover you. Maybe you could install the chimney yourself?
 
dgarver said:
BrotherBart said:
Nope. No power venting a wood stove. Having a full load of wood burning and having a power vent fail would be a disaster like you haven't seen. With oil, gas and pellet at least they can shut down. You can't yell "whoa" at a flaming load of wood and get any results.

And yes for the record Consumer Reports said in an article that you could use a power vent. They were wrong.

Assuming the power never failed, would it work>? I have a battery backup system, I would be running a 12v fan on a trickle charger and marine battery.

It doesn't matter if you could use a power vent or not, (which you can't) , you still need a proper chimney period. More on power vent, a power vent hooked up to a wood stove could also be described as a blast furnace, a device use to melt iron and steel. Just plain bad, never mind the power issue. The difference between any other fueled apliance (included a pellet stove) and a wood stove is that the other apliances METER the fuel. A woodstove does not. Your stove could literaly melt given any number of untoward circumstances, even too dry wood would be extremely dangerous.

As to the outside chimney controversy, build an insulated chase around the chimney. It will work better and look nice too. Or not. If you have draft problems you can add a chase later. If it were me, I would run it inside the house. I have no problem whatsoever with a hole being cut in the roof properly.
 
SKIN052 said:
Seriously, please do not do what you are thinking, it is unsafe and your insurance would never cover you. Maybe you could install the chimney yourself?

I'm not sure why you have your heart into this 'power vent' idea, even thoughts of what to do in a power outage. Yet you are scared to death to put a chimney up the side of the house or through the roof. Is it a cost cutting idea? If so cutting corners on a solid fuel burning heater will only bring trouble.
 
A few things. Consider using an existing fire place chimney with a liner or if your home is older it may have a brick or block chimney which you could add a liner to and run a add on furnace. Reconsider placement of the stove to a room which may not have a second story above it. Build a chase and use a insulated liner, which would look better.
Yes, the pipe is expensive but these are up front costs which will be paid back everytime you pay your heat bill. Don't forget 30% tax credit up to $1500, until 12/31
 
Welcome! I hope you find this group as friendly and educational as I do.

Regarding power-venting a wood stove, it's a bad, bad, bad idea, and you'll have to do a lot of looking around to find someone somewhere who'll tell you it's okay.

Take it from me--I can be very stubborn and non-conformist, and even *I* think you'd be better off just setting your house on fire right now, and getting it over with. At least you wouldn't have spent the time and money on stove and installation, no one would die, you could get your stuff out first, and maybe your insurance would pay for it.

How about posting photos, and/or a diagram of where you'd like to put your stove, and the experts here can help design a safe and functional chimney? The chimney and stove work together as a system, and installing a good chimney isn't sexy, but necessary. (And yes, forum, I am reading my own words, chuckle.)
 
Thanks for the input so far guys. No, I am not nuts, I swear. Yes the idea is simply cost cutting, as we just don't have an extra 800-1,000$ to throw into a chimney, when our wood stove won't even be costing us that much. As for the power blast furnace idea, maybe I am using the wrong terminology? I will be installing the chimney myself, so labor is not an issue. We have no existing chimney, and the house is only 4 years old. We will need about 15' of height on our chimney, and that cost added to the wall pass through kit and the stove pipe itself is astronomical compared to the vent setup on a pellet stove. Hence, the reason I was interested in that concept. But, that is obviously out. As for the roof, I have never done any sort of roofing, so I would need to make sure I had something to reference to show me how to seal the penetration properly, not too mention it would be running up through our second story office, which may or may not be a bad thing? It would look hideous, which I wouldn't mind, but when we sell the house it may detract from it's value. I suppose we could box it in at a later date, but then it is removing usable space. So-all of this being said, maybe I should instead ask where the best priced chimney kits are? Is there a fire code that says they must be stainless steel, or can they be galvanized?
 
Class A can be expensive, yes, but the chimney is the engine that drives the entire system by pulling warm air upwards and creating the necessary draft to drive the stove. Keep in mind that flue gases can reach 1,000F when charring a fresh load of wood, so you want a UL tested system that you can place your full confidence in. A properly installed and tested chimney is as least as (if not more) important than the stove.

My flue is interior and penetrates a second floor living space. It went through the corner of my oldest daughter's bedroom, and it is boxed in with the proper clearances. Sure, we gave up a little living space, but it resulted in a straight shot from stove to daylight, and it drafts magnificently.

If price is a major concern, try several sources: box stores like Lowe's often carry one of Selkirk's line, and it is good stuff. You can also try online retailers like www.northlineexpress.com if you are comfortable with that. And always check your local mom and pop hearth stores.
 
Pagey said:
Class A can be expensive, yes, but the chimney is the engine that drives the entire system by pulling warm air upwards and creating the necessary draft to drive the stove. Keep in mind that flue gases can reach 1,000F when charring a fresh load of wood, so you want a UL tested system that you can place your full confidence in. A properly installed and tested chimney is as least as (if not more) important than the stove.

My flue is interior and penetrates a second floor living space. It went through the corner of my oldest daughter's bedroom, and it is boxed in with the proper clearances. Sure, we gave up a little living space, but it resulted in a straight shot from stove to daylight, and it drafts magnificently.

If price is a major concern, try several sources: box stores like Lowe's often carry one of Selkirk's line, and it is good stuff. You can also try online retailers like www.northlineexpress.com if you are comfortable with that. And always check your local mom and pop hearth stores.

The warm air drafting upwards is what I was talking about doing with the fan. But I understand what you are saying. We simply do not have the funds right now to do it as you describe. This looks like it will need to wait. Thanks.
 
We simply do not have the funds right now to do it as you describe. This looks like it will need to wait. Thanks.

That's the right decision. Much better than burning your house down.

The upside is, you can start collecting firewood now. The longer it sits, the better your stove will work.
 
Time to look at the core decision. If you are cost cutting, go up through the building through the roof. The stove will function much better, the flue will run cleaner and it is usually less expensive. This really is the best way to go.
 
A vent seemed cheep at lowe's, We installed a 6" vent with all the parts for around 700 bucks.
We went up thru the first floor with black pipe and then16' thru the second floor roof area and 30" above the ridge of the house
Its better to run the pipe inside the house . John
 
wellbuilt home said:
We went up thru the first floor with black pipe

You must have typed that wrong? I hope. Black pipe cannot penetrate a floor or ceiling.
 
Seems to me if you can't afford the venting, you can't afford to do it. We paid $1200 for our used Oslo, and $2750 for the pipe, (304 single wall stainless), chimney cap & installation up a chimney.
 
FWIW there does exist a power vent that works with a chimney, called the Exhausto, but it's primarily meant to shore up inadequate draft in certain conditions (especially found with fireplaces) and it's still expected to be installed on a safe, working vertical chimney that goes above the roofline. It's also very expensive from what I gather. IOW, not worth it. Do it right the first time with a properly installed class A chimney and be happy!

Consider this the hidden cost of the woodstove -- The stove is cheap, but that's because it relies on a chimney which will cost $$ if you don't already have it.
A pellet stove is expensive, but includes the engine to drive the venting system (i.e. the electric-powered combustion fan), and I'd imagine pellet pipe isn't as expensive as class A metal chimney pipe (or at the very least you need less of it.)
 
I'd be reallllllllllly suprised if the exhausto fan is code approved for a woodstove.

Dune (among many others) hit the nail on the head - power vents work with pellet, oil and gas units because all of those control the burn rate primarily by metering the fuel. A wood stove on the other hand controls the fire by metering the air input. Anything you do to force airflow removes your ability to control the fire. Result is a molten slag pile in your living room :(
 
dgarver, I am glad to see you came here and asked, instead of just installing what could easily become your worst nightmare.

Merry Christmas to you, and your family.
 
dgarver said:
One shop told us we couldn't or at least shouldn't run our chimney out through our wall and up the side of the house. We have a two story home, and absolutely do not want to punch a hole through the roof.
Sage advice from a shop prepared to lose a sale rather than compromise their integrity. Yes, you will find like-minded people here that also didn't want to poke a hole through their roof and yes, they will give you all sorts of success stories but YMMV.

My advice... go through the second storey and through the roof. A warm chimney with a straight-up run is always better. Right angles and Tees are places for creosote to collect in and chimney fires to take hold. They also reduce the draft as does a cold outside chimney.

Maybe you should go with a pellet stove or an OWB instead.
 
not too mention it would be running up through our second story office, which may or may not be a bad thing? It would look hideous, which I wouldn't mind, but when we sell the house it may detract from it's value. I suppose we could box it in at a later date, but then it is removing usable space. So-all of this being said, maybe I should instead ask where the best priced chimney kits are? Is there a fire code that says they must be stainless steel?

I've never installed double wall flue pipe myself in the interior of a home but I am aware the building code will come into play when holes are opened to make way for the pipe. An air space is created and I believe the pipe would also have to be enclosed in this type of living space (an office) as well. I opened up some sections between 2 floors for a plenum and had to fire block and insulate inbetween floors.
 
Class A pipe running through living space on an upper floor has to be chased in if it is in reach of being touched.
 
If you're holding off for now on this, but are thinking of doing it in the future, it's a good time to start collecting wood. Another important part of wood stove operation is having dry fuel (often overlooked).
 
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