Thinking about modifying stove...

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brooktrout

New Member
Hearth Supporter
Dec 23, 2007
376
Hamden, NY
I have been reading a lot about the air was system, and how many of today's stoves have their draft controls located near the top of the stove. Mine are at the bottom, one slider in each door. I was thinking about altering the stove and adding draft controls near the top. Is there a diff. as far as efficiency is concerned?
 
Once you modify it you are the new manufacturer. You void the listing if it even has one. Insurance wont cover your house if it burns down and the inspector finds the modifications.
 
If you add draft controls at the top you may have smoke pouring out those holes. Does it have a baffle inside the firebox? Baffles will help along with firebricks to heat up the box enough for secondary combustion.
 
What do you mean by baffle? Not the same as damper, I assume? So, it's possible to get secondary combustion even though it's not a cat? Explain, please- and how will I know when this occurs? Is is something I can see through the glass? Thanks. If I added draft controls to the top, I would make them so they can be closed airtight. Just wasn't sure if there was a burning efficiency diff. in locations of draft inlet...
 
Well, one thing you don't have to worry about is losing the stoves UL listing. The 1987 Buck Stove 28000 never was UL listed in the first place.
 
jtp10181 said:
Once you modify it you are the new manufacturer. You void the listing if it even has one. Insurance wont cover your house if it burns down and the inspector finds the modifications.

Actually, his insurance carrier likely would provide coverage for repairs to the house. There's a saying in the insurance industry ...... "there's no exclusion in the policy for stupid" BTW I am not implying his idea is stupid. I'm only saying that, home owners build, fix, modify, things all the time. Unfortuneatly, sometimes things don't work out as planned and fire or other failures occur that end up causing damage to the building.
 
Brooktrout,

Please tell us how you are going to keep the smoke and flames from billowing out?

Thank you in advance!
 
Jim Walsh said:
Brooktrout,

Please tell us how you are going to keep the smoke and flames from billowing out?

Thank you in advance!
I suppose that if the smoke and flames don't come out of the bottom draft controls, why would they come out of the top, as long as you are using one or the other? I'm not sure, that's why I am here seeking advice. No one has replied as to whether they feel a top mounted draft versuses bottom is more efficient.
 
brooktrout said:
What do you mean by baffle? Not the same as damper, I assume? So, it's possible to get secondary combustion even though it's not a cat? Explain, please- and how will I know when this occurs? Is is something I can see through the glass? Thanks. If I added draft controls to the top, I would make them so they can be closed airtight. Just wasn't sure if there was a burning efficiency diff. in locations of draft inlet...

No, not a damper. The baffle is inside the firebox, usually made of steel, firebricks or some kind of ceramic board. Basicly the baffle creates an S pattern inside the firebox creating more heat and secondary combustion. Check this out from woodheat.org.

www.woodheat.org/technology/woodstoves.htm
 
Todd said:
brooktrout said:
What do you mean by baffle? Not the same as damper, I assume? So, it's possible to get secondary combustion even though it's not a cat? Explain, please- and how will I know when this occurs? Is is something I can see through the glass? Thanks. If I added draft controls to the top, I would make them so they can be closed airtight. Just wasn't sure if there was a burning efficiency diff. in locations of draft inlet...

No, not a damper. The baffle is inside the firebox, usually made of steel, firebricks or some kind of ceramic board. Basicly the baffle creates an S pattern inside the firebox creating more heat and secondary combustion. Check this out from woodheat.org.

www.woodheat.org/technology/woodstoves.htm
Okay, I see- thanks for the link. It would be great if a baffle could be retrofitted to older stoves to accomplish this. More research...
 
One reason that air is let into the top of the doors is that it instantly falls and helps keep the glass cleaner. Some stoves simply left out the gasket at the top of the glass, in order to let a little bit of air come in and wash across the glass.

In general, I think it will be hard to increase the efficiency of older stoves by fiddling with them. Maybe a pipe damper will do something in certain situations - or even a miracle heat (blower thingy).
 
Brooktrout,

That is all about what the EPA and clean air tried to do with the stove manufacturers.

Even old Ben Franklin stoves and old coal stoves tried to move as much unburned material back into the firebox. So reheating, reheating, reheating as much unburnt material and then letting out enough exhaust to keep the fire/coals going.

Here is the basic design of my stove:
Thinking about modifying stove...

On the right hand side, this is the way I start it up, the smoke and heat goes right up the flue.

On the left hand side with the damper closed, the heat is trapped on the upper part of the box and the exhaust fumes have to enter the lower part of the box to exit. Air is mixed in across the fireback which is an internal plate.



Unless I close my damper, only the front,left side, and top of the stove get hot. When I close the damper, the hot exhaust goes through the lower chamber on the right side of the stove, circulates behind the fireback and heats the back of the stove and then exits through the exhaust. Real simple principles here but most non-EPA boxes were just that... a BOX.. letting all the heat escape.

Thinking about modifying stove...

Thinking about modifying stove...

Notice the primary and secondary air intakes and where the air is brought in as per circulation. Everything here is on the lower end, the reason is to keep the hot gases and unburned material at the top of the fuel chamber.

Now that I have thoroughly confused you/us... build us a better box. That is what ingenuity is all about.
 
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