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I see about one wood burning stove every four years so this isn't my strongest area [:-dunce]icon_speech_sigh.gif.

The clearance on the back of the stove is probably no more that 8".

The back wall is a happy homeowner special with various rock types mortared together. There is nothing behind the stone but wood paneling.

There is about an 18" clearance on the front pan.

The stove sits in a framed area that is filled with river rock which sits on the sub-floor. There is only 4" to 6" clearance on either side of the stove.

There are other issues with the flue but I'm not sure of the placement of the stove and the use of the loose stones being both safe or meeting codes.

Please help with your opinion of this install.

Thanks,

Jeff Beck

Foresight Home Inspection

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I rarely see freestanding stoves either, but based on my experience in installing a couple different ones, your install is all wrong. Typically, the side hearth extensions need to be larger. The rear clearance is also seriously inadequate -- especially without any heat shield either on the stove or behind the stone. Keep in mind that while the rock won't burn, with extended run times, heat soak will occur and the paneling behind it could ignite. Also, I can't see that loose stones would qualify as a noncombustible hearth extension since embers could make their way down between the stones to a combustible wood floor below -- if that's what you have.

That may be a vintage unit with no manual available. Even without one, there are a lot of obvious issues and referring it to an expert would be prudent.

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Originally posted by Jeff Beck

I see about one wood burning stove every four years so this isn't my strongest area [:-dunce]icon_speech_sigh.gif.

The clearance on the back of the stove is probably no more that 8".

The back wall is a happy homeowner special with various rock types mortared together. There is nothing behind the stone but wood paneling.

That's a very old wood stove. It probably dates from the late '70s and is almost certainly unlisted. The manufacturer is probably out fo business. There won't be any manual around and, in fact, it might not have ever had a manual.

NFPA 211 requires 36" of clearance between an unlisted stove and a combustible wall surface. That means that a 36" long string attached to any point on the stove shouldn't be able to touch the paneling.

If there's a proper clearance reduction system in place, you can reduce that clearance to 12". However a proper clearance reduction system requires an air space behind it.

The stove installation in your picture doesn't come close to those requirements.

There is about an 18" clearance on the front pan.

The stove sits in a framed area that is filled with river rock which sits on the sub-floor. There is only 4" to 6" clearance on either side of the stove.

There should be 18" in front and 18" to either side. The loose river rock is almost certainly not acceptable per NFPA 211. What was the clearance under the stove? There are different requirements that depend on that dimension.

There are other issues with the flue but I'm not sure of the placement of the stove and the use of the loose stones being both safe or meeting codes.

Please help with your opinion of this install.

It's not safe. That stove is very primitive by modern woodstove standards. It has a lousy door design that can't be well sealed and the firebox is very inefficient. As a result, fires built in it will burn very hot. Lots of energy will be wasted up the flue, but you'll also get very high temperatures on the surface of the stove. It'll radiate outward and really heat up the walls, the stones & the floor. If the residents are imprudent in their firebuilding habits, something could get hot enough to ignite outside the stove.

In Oregon, you wouldn't even be allowed to fix that installation. A pre-DEQ stove with a non-compliant installation would have to be ripped out and sent to a scrap dealer. You wouldn't even be able to sell it or install it in your shop. It'd have to be destroyed.

Washington may have a similar law.

- Jim Katen, Oregon

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It's not safe. That stove is very primitive by modern woodstove standards. It has a lousy door design that can't be well sealed and the firebox is very inefficient. As a result, fires built in it will burn very hot. Lots of energy will be wasted up the flue, but you'll also get very high temperatures on the surface of the stove. It'll radiate outward and really heat up the walls, the stones & the floor. If the residents are imprudent in their firebuilding habits, something could get hot enough to ignite outside the stove.

Identical stoves are still manufactured today. It's not supposed to be a modern, efficient, rope-sealed door stove. In fact, it was intended to operate with the doors open, until the end of a period of use.

It's a "Franklin stove", although not exactly Franklin's original design of 1742 (it didn't work). Franklin liked the heating ability of the recent German settlers' five-plate stoves, but he didn't like the fact that one couldn't see the fire. His design was a compromise, but was intended to be significantly more efficient than an open fireplace. David Rittenhouse improved Franklin's concept in 1772 so it would vent properly. He called it the "Rittenhouse Stove", which is still the same exact design as in Jeff's pic. Everyone calls it the Franklin stove to this day.

It's almost impossible for most folks to be able to determine if one were manufactured 200 years ago or last year. They're still quite popular around these parts. If Jim were to make his comments to any Franklin stove owners in the city of Fluffia, PA or surrounding counties, I'm sure they would try to do him some bodily harm.

NFPA 211 requires 36" of clearance between an unlisted stove and a combustible wall surface. That means that a 36" long string attached to any point on the stove shouldn't be able to touch the paneling.

If there's a proper clearance reduction system in place, you can reduce that clearance to 12". However a proper clearance reduction system requires an air space behind it.

If the masonry on the wall is consistently at least 3.5" thick, without a ventilated air space, the required clearance can be reduced by 33%.

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Originally posted by inspecthistoric

It's not safe. That stove is very primitive by modern woodstove standards. It has a lousy door design that can't be well sealed and the firebox is very inefficient. As a result, fires built in it will burn very hot. Lots of energy will be wasted up the flue, but you'll also get very high temperatures on the surface of the stove. It'll radiate outward and really heat up the walls, the stones & the floor. If the residents are imprudent in their firebuilding habits, something could get hot enough to ignite outside the stove.

Identical stoves are still manufactured today. It's not supposed to be a modern, efficient, rope-sealed door stove. In fact, it was intended to operate with the doors open, until the end of a period of use.

It's a "Franklin stove", although not exactly Franklin's original design of 1742 (it didn't work). Franklin liked the heating ability of the recent German settlers' five-plate stoves, but he didn't like the fact that one couldn't see the fire. His design was a compromise, but was intended to be significantly more efficient than an open fireplace. David Rittenhouse improved Franklin's concept in 1772 so it would vent properly. He called it the "Rittenhouse Stove", which is still the same exact design as in Jeff's pic. Everyone calls it the Franklin stove to this day.

Sure, it's a 250 year-old technology and grossly inefficient by modern standards. If Ben were around today, he'd toss that thing in the scrap heap and embrace something much more efficient.

It's almost impossible for most folks to be able to determine if one were manufactured 200 years ago or last year. They're still quite popular around these parts. If Jim were to make his comments to any Franklin stove owners in the city of Fluffia, PA or surrounding counties, I'm sure they would try to do him some bodily harm.

Really? I'm shocked. Doesn't PA subscribe to the Clean Air Act? (And is there really a town called Fluffia?)

I know that Oregon tends to be more environmentally conscious than many other states -- our woodstove rules are positively draconian -- but I figured that PA would, at least, require an EPA cert on woodstoves.

- Jim Katen, Oregon

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Sure, it's a 250 year-old technology and grossly inefficient by modern standards.
We had a 300 y-o house that one of the fireplaces could easily fit most mini-vans. We loved it, but we had to seal the door to the boiler room and open up some windows when we fired it up. I inspect several homes with open-hearth fireplaces each week. It's a major desirable feature of the home. If I suggested to buyers to put in a Quadrafire, I'd get punched in the face. It ain't about modern standards.
Really? I'm shocked. Doesn't PA subscribe to the Clean Air Act?
Hell no- we cook breakfast over an anthracite grill!
(And is there really a town called Fluffia?)
Since youse not from here, I getst you wootna known it's houz we sez Philadelphia.
I figured that PA would, at least, require an EPA cert on woodstoves.
Nope. Here in rural areas, we can burn trash in open pits too. In PA, we let a coal vein fire destroy a town and it's still burning 45 years later.

[utube]http://www.youtube.com/watch?v=fkHfnp2czZQ" type="application/x-shockwave-flash" wmode="transparent" width="425" height="344">

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I don't get it; why didn't they just take a low tech approach and divert a danged creek into that mine and fill it with water? If they found it draining out through some other abandoned mines they could cave those in. Surely it would have filled up decades ago and then they could have waited a decade or so before draining it to make sure the whole thing was out. Bet that wouldn't have cost anywhere near $600M. It seems like gross negligence just to allow it to continue to burn unhindered for this long.

Aw, waddu I know. The clock still blinks on my VCR after 13 years.

ONE TEAM - ONE FIGHT!!!

Mike

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Originally posted by hausdok

I don't get it; why didn't they just take a low tech approach and divert a danged creek into that mine and fill it with water? If they found it draining out through some other abandoned mines they could cave those in. Surely it would have filled up decades ago and then they could have waited a decade or so before draining it to make sure the whole thing was out. Bet that wouldn't have cost anywhere near $600M. It seems like gross negligence just to allow it to continue to burn unhindered for this long.

Aw, waddu I know. The clock still blinks on my VCR after 13 years.

ONE TEAM - ONE FIGHT!!!

Mike

Got a topo map?

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I'd be pretty concerned not only with the clearances to the wall, but to the subfloor with this one........

I get the point of people liking these stoves, and I understand they will use them. Can't they at least build in adequate clearances to prevent fires?

I'd be interested to see how hot the wall and floor framing would get when there's a rip roaring fire burning for an extended period of time.

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I don't think that it has been mentioned but not only does the stove have to go but also the entire vent system. Stoves today are tested and rated for use with specific vents. This should be kept in mind if even a relatively new stove was being replaced. Just looking and fitting the same isn't good enough. Ever price out a new vent system?

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  • 11 months later...

HAPPY NEW YEAR 2010 FROM THE EUROPEAN UNION TO THE STATES!

=========================================================

I'm tremendously happy that the thread with experts survived over a year!

I have got nearly the same Franklin stove as Jeff's, though of an infernal Chinese quality, at least as far as its poor (unwanted) door clearances are concerned. The Chinese have made them on the contrary more apparent rather than rope sealed, probably due to the more strict requirements for pollutions and better combustion. Also, I can see some appliances inside of Jeff's stove, which are not provided in my stove. I can't guess, what they are for. Please, do explain it.

I have made this choice because this stove delivers the medically important radiant warmth through radiation, unlike all modern wood stoves delivering warm air only.

However, the costs of fuel in urban areas have dramatically raised within the last years.

So, the costs let me be thinking how to improve the efficiency of my stove if not to conceive constructing a more efficient one -- for my particular needs and requirements.

I've got some experinces with this stove. Now, I could say that the normal wood consumption is some 15-20 pounds of briquettes (quite common in Europe now) -- 8 to 16 pieces per night. - I've been told that with a modern stove construction the wood consumption would be much less than that.

The hume evacuation pipe has a length of some 10 feet and the diameter of some 8 inches, which should provide nearly the same radiant surface, as that of the stove itself.

So, I would like to know, whether I would really get any real improvement in consumption of wood if I would introduce a tube for air and oxygen supply and secondary combustion, and make the doors rope sealed?

Thanks.

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I dunno,

Sealing the doors might slow down combustion and prevent some interior air/heat from being sucked up the flue but if it uses interior combustion air now you're going to need to bring in exterior air somehow so it will combust properly. I wouldn't use any kind of a fan to do that or you could end up forcing CO into the home. It needs to be natural draft.

I don't think you'll get any improvement in consumption by increasing air to the box. I think it's liable to burn hotter and more rapidly.

I think the key to getting a lot of heat out of a wood burner is how the mass of the refractory brick is used. I've seen pellet stoves with large refractory surfaces produce heat equal to large fires in unlined stoves using only a handful of pellets.

ONE TEAM - ONE FIGHT!!!

Mike

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I don't think you'll get any improvement in consumption by increasing air to the box. I think it's liable to burn hotter and more rapidly.

Mike

Thanks, Mike, for the idea to burn hotter and more rapidly.

However, the specified power of the stove is 12 kW.

To make it warm, one would need to burn at least 4 briquttes at a time.

However, the grate takes 6-8 pieces at large.

That implies that a go would have 10-16 pieces per night, which is right my case.

The problem is: How could I attain any material / financial economy with this stove?

My idea of improvement would be as follows.

The stove doors have 2 air intakes sized about 1 inch x 1 inch. The one serves to deliver air for combustion in the bottom of the stove. The other could be used for introducing and fixing an S-like air duct to deliver preheated air for secondary combustion above the flame; the duct can be made of stainless steel.

Secondary combustion would rise the temperature inside of the stove while the flue to the chimney could be damped.

Sealing the doors would be assistent to the above process.

I am mistaken, am I not? Where, then?

Alex

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Mike,

Being unprepared, I cannot think of the refractory brick so far. At the moment, I have 3 thin metallic screens placed at a distance of some inches on the 3 sides of the stove to reflect back the radiation made by the stove in order to keep safe the things around. I wonder, but the screens remain always chilly.

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