why cant u power vent a wood stove>?

[SmokeyCity]

like coal and gas stoves can?

 

[North of 60]

#1 Why would you want to. With a correct install it is not required.
#2 Would have to be a stove as part of the design as controlling the burn would be key as your fuel supply will not be consistant.
#3 A pellet stove or wood boiler is the best application for this as they are designed for it..
#4 Power is required for this to operate properly which rules out redundancy.
A few of my thoughts.
Cheers!

 

[fossil]

You would no longer have a listed and certified solid fuel-burning appliance. You would have a dangerous inadvisedly modified and unpredictable forge. Please evacuate your loved ones from the premises before you fire something like this up. Rick

 

[Martin Strand III]

Wood stoves were not designed to be power vented.
Power venting will
* easily over fire a wood stove
* decrease safety and longevity
* increase fuel consumption
But, that doesn't mean you can't do it.
It's just not a good idea.

You can burn nitrous oxide in your car's engine
for increased performance too.
Unless you have the know how and
a specific reason to do so,
it's not a good idea.

You can start your wood stove fires with flammable
liquids but that's not a good idea either.

Aye,
Marty
Grandma used to say, "Common sense is not so common."

 

[bpm44]

You would essentially be making it a forge.

Metalsmithing anyone? I'm sure a Smithy could provide some good detail.

 

[wkpoor]

I don't think he is asking to do it himself. Basically I see him asking why can't they be power vented. I would say because wood stoves are air cooled and can easily run at optimum temperatures without the aid of forced combustion. Wood fired boilers on the other hand are water cooled and have a much greater demand for absorbing BTUs.

 

[SmokeyCity]

Best Answer :=)
voted by asker....
LOL

You would no longer have a listed and certified solid fuel-burning appliance. You would have a dangerous inadvisedly modified and unpredictable forge. Please evacuate your loved ones from the premises before you fire something like this up. Rick

 

[LLigetfa]

Some OWB have powervents, mainly because of the short flue but also cuz it's safer to do it outside. Simply as others said, indoor wood burners don't need it. If a home was so poorly balanced that natural aspiration didn't work, powerventing could push CO and smoke out of every crack and joint in the stove, stovepipe, and chimney.

 

[raybonz]

Part of the problem would be if the blower stopped it would create a restriction in the flue and the stove would burn merrily on.. This would pose a hazard as carbon monoxide could enter your home if the smoke cannot vent through the flue. With a pellet stove, gas or oil furnace the burn cycle stops when power is lost whereas wood keeps burning.. Then there is the increased draft issue that was mentioned to possibly create a blast furnace but I would think the blower is more of a draft enhancer rather then a positive force blower.. I could be off base but that's what I am thinking right now..

Ray

 

[agartner]

This thread reminded me of an interesting curiosity. Many, many years ago, before I was a woodburner, we stayed at a small hotel or lodge up in Northern NH for the weekend. In our room was a big old cast iron woodstove, and installed inline on the stove pipe was a power blower. The hotel had posted some instructions - load the stove with wood and kindling - I think they even provided some kind of firestarter too, turn the blower on, light the fire, and turn the blower off after about 15 minutes.

I remember doing it, getting warm, and not dying. Don't remember much more beyond that though.

 

[DanCorcoran]

"Don’t remember much more beyond that though. "

Yeah, carbon monoxide will do that...

 

[LLigetfa]

...and installed inline on the stove pipe was a power blower.

That "sucker" is what's often called a draft inducer. While it blows, in reality it is sucking from the stove.

What I described earlier was a combustion air blower that sucks clean cold air. I've not looked closely at all pellet stoves but I think they mostly blow air into the stove and not power vent the exhaust. I expect some do both.

 

[babzog]

...and installed inline on the stove pipe was a power blower.

That "sucker" is what's often called a draft inducer. While it blows, in reality it is sucking from the stove.

What I described earlier was a combustion air blower that sucks clean cold air. I've not looked closely at all pellet stoves but I think they mostly blow air into the stove and not power vent the exhaust. I expect some do both.

I have to rig something like this to get my basement stove going when it's back drafting but I remove the fans once it's lit.

 

[chimneyguy]

Hi,
If it's smoking, make sure there is at least 12' from the firebox floor to chimney top (about the minimum that is needed to establish a good draw), and try opening a nearby window. If open window helps, house is depressurized and makeup air is being supplied by the stove chimney... see John Gulland's book elsewhere on this site for a thorough discussion...
Generally, as others say here, not usually necessary or well advised. As to why this hasn't been done much, simpler = better.
Stay warm,
Ed

 

[Dune]

The main problem is simply the inability to meter wood as a fuel, hence leading to overfiring.

I have to assume the question is being asked in an attempt to simplify exhaust installation.

Sorry, it's just not going to happen.

 

[firefighterjake]

The main problem is simply the inability to meter wood as a fuel, hence leading to overfiring.

I have to assume the question is being asked in an attempt to simplify exhaust installation.

Sorry, it's just not going to happen.

I suspect this is a large reason . . . with oil or gas a certain amount of known fuel is pumped or sent to the burn chamber where it ignites and produces a know quantity of gas, heat, etc. . . . with firewood you do not have a known quantity that will produce X, Y and Z every time it burns.

Another possible reason could be that when the power goes out with a gas or oil boiler the fuel source is no longer sent to the burn chamber and there is no ignition source . . . if a woodstove had a power blower there is no easy way to simply stop the wood from burning and there would be a danger of smoke in the building, CO, etc.

Well, that and the aforementioned forge effect . . .

That said . . . I wonder if you couldn't use a power exhaust on a pellet boiler or furnace . . . just thinking . . . not that I am saying I would do so . . . just wondering if a manufacturer could do so . . . although I suspect with such a short run required with these types of heating units it wouldn't make sense to have a powered exhaust for the expense.

 

[Dune]

The main problem is simply the inability to meter wood as a fuel, hence leading to overfiring.

I have to assume the question is being asked in an attempt to simplify exhaust installation.

Sorry, it's just not going to happen.

I suspect this is a large reason . . . with oil or gas a certain amount of known fuel is pumped or sent to the burn chamber where it ignites and produces a know quantity of gas, heat, etc. . . . with firewood you do not have a known quantity that will produce X, Y and Z every time it burns.

Another possible reason could be that when the power goes out with a gas or oil boiler the fuel source is no longer sent to the burn chamber and there is no ignition source . . . if a woodstove had a power blower there is no easy way to simply stop the wood from burning and there would be a danger of smoke in the building, CO, etc.

Well, that and the aforementioned forge effect . . .

That said . . . I wonder if you couldn't use a power exhaust on a pellet boiler or furnace . . . just thinking . . . not that I am saying I would do so . . . just wondering if a manufacturer could do so . . . although I suspect with such a short run required with these types of heating units it wouldn't make sense to have a powered exhaust for the expense.

Pellet stoves already use a short horizontal disharge anyway, so no need really.
Also good point about the instant shutoff of the fossil fuel burners when the power goes out.

 

[SolarAndWood]

After seeing what happens when the blower fails on a power vent that has had the interlock defeated, I never want one in any building I own. What a mess and lucky the house didn't burn down with everyone in it.

There is no way to get a chase up the side of the house?

 

[mrfjsf]

why cant u power vent a wood stove>?

cause, you'll shoot your eye out!

 

[Eaglecraft]

Wood stoves were not designed to be power vented.
Power venting will
* easily over fire a wood stove
* decrease safety and longevity
* increase fuel consumption
But, that doesn't mean you can't do it.
It's just not a good idea.

You can burn nitrous oxide in your car's engine
for increased performance too.
Unless you have the know how and
a specific reason to do so,
it's not a good idea.

You can start your wood stove fires with flammable
liquids but that's not a good idea either.

Aye,
Marty
Grandma used to say, "Common sense is not so common."

Your grandma was pretty smart, as was Voltaire: “Common sense is not so common.â€

The Volemister

 

[sebring]

You could powervent a wood stove. BUT for the price its not worth trying. 300-500 dollars for the good ones, and thats doing the installation yourself. A SS chimney from lowes is a little more, and a million times safer. I believe the powervents I saw reduce down to 4" and the end looks like it could clog with creasote quickly. Im guessing the motor wouldnt last very long running all winter, so add that price also.

 

[woodmiser]

They powervent oil and gas appliances because they can be totally shut down in a instant if the power vent shuts down. They typically use a vacuum switch and use some electronics. Usually when a thermostat calls for heat, the vent starts first before the burners, for a short time to purge the exhaust of any fumes. When the blower is running it creates a vacuum in the exhaust vent. The vacuum switch is connected to the exhaust. If there is no vacuum, the burner will not start. If the blower dies, the burner shuts off. If the exhaust gets restricted in any way, the burner shuts off.

So the biggest problem with using a power vent on a wood stove is if something causes the blower to shut off, there is no immediate/instant way to shut off the "burner".
And if you think you can vent out the side of the house with it, think again as that smoke and heat will surely be hazardous at levels close to the house.... Codes would never allow it.

 

[DexterDay]

...and installed inline on the stove pipe was a power blower.

That "sucker" is what's often called a draft inducer. While it blows, in reality it is sucking from the stove.

What I described earlier was a combustion air blower that sucks clean cold air. I've not looked closely at all pellet stoves but I think they mostly blow air into the stove and not power vent the exhaust. I expect some do both.

Older model pellet stoves (some) had a positive pressure firebox, where all new stoves are designed to be negative pressure fireboxs (w/ vacuum safety switch) and rather "pull" the air through the stove. Exhaust is the only positive pressure in the unit. All for safety reasons. A leaky door gasket on an older model would result in CO leaking into the home. Newer models with leaky gaskets just produce a a bad burn and/or incomplete combustion. Much safer this way.

Pellet stoves use a pretty consistent fuel, where depending on the user (and there wood) the power vent wood stove wood have a lot of varibles. Just regular draft creates gobs of heat. I can only imagine the amount of heat that 3 cu ft of wood could produce if air was blasted into the firebox. Overfire anyone??

Pellet stove info is Not really related to thread. But just in case anyone was wondering.

 

[DAKSY]

While technically NOT a Power Venter per se, I have installed
these on basement-located woodstoves, where the stove being
below the pressure plane of the house was nearly impossible to
start without a lot of back-puffing...

http://www.exhaustofans.com/