Wide open burn....

[gerry100]

I've been heating with wood for 29 years and am glad it's resurging.

Can't wait to fire up the new Country Canyon that replaced old "Jumbo Moe".

But I'm anticipating a lot of chimney fires with new burners this winter as they learn to control the new stoves.

The same urge that makes us turn up the new stereo as loud as it goes or see how deep the mud is we can ge tinto/out of with the new Jeep etc will make some see how much they can load stove and how long they they can burn and or how well they can control the temp with the levers or knobs.

WRONG.

Default setting for the stove should be wide open air with the temp controlled by the size/amount of pieces you put in.
This is a little more work initially but results in a clean, hot ,very low creosote burn.

After a while , one can almost instinctively control the room temp by tossing in the right piece of wood periodically. It's part of the fun.

Only when setting up the stove for overnight should it be fully loaded and choked down ( one also learns this by trial and error).

In the morning, open it wide open and run it hot. This will clean up the deposits from overnite and start the daily burn cycle again.

STAY AWAY FROM THE KNOBS AND LEVERS.

 

[BrotherBart]

I am anticipating that you have a lot to learn about modern wood stoves. ;-)

 

[Noah]

I noticed that I don't get a good secondary combustion with the draft open all the way.

 

[bluefrier]

Default setting for the stove should be wide open air with the temp controlled by the size/amount of pieces you put in.
This is a little more work initially but results in a clean, hot ,very low creosote burn.

not with an epa secondary burn stove. In my opinion (at least on my stove) the cleanest burn is with the damper almost fully closed after the
stove gets up to temp.

 

[bluefrier]

I am anticipating that you have a lot to learn about modern wood stoves. ;-)

LOL :lol:

 

[gerry100]

I'll keep an open mind and try it both ways.

Can anyone explain the theory behind less air/clean burn in the new stoves?

 

[cmonSTART]

Yup, my air control gets choked back to about 20 to 25% after the fire's rolling and there's some nice coals established. Nice long, hot, clean burn there.

Although, if I remember correctly, I think John Gulland recommends varying your heat output by wood amount/type first, then the air control.

 

[WOODBUTCHER]

Most of the time my Oslo draft control is between 10-25% open, otherwise I'm looking at temps beyond 700 degrees.

WoodButcher

 

[fossil]

I throttle the air on both my stoves after a good fire's established...if I didn't, I'd probably burn 15 cords/season instead of just 7, and we couldn't stand to be in the rooms with the stoves. Room & stovepipe temps stay pretty much right where they should be. Rick

 

[bluefrier]

I'll keep an open mind and try it both ways.

Can anyone explain the theory behind less air/clean burn in the new stoves?

Try this link: (broken link removed to http://www.chimneysweeponline.com/horeburn.htm)

 

[BrotherBart]

I'll keep an open mind and try it both ways.

Can anyone explain the theory behind less air/clean burn in the new stoves?

A big part of it is that fixed secondary air is introduced at the top of the firebox no matter what the primary air adjustment setting is. And that primary can't be closed down all the way either. If you leave the primary wide open with small loads the unburned gases exit the firebox too fast for them to be combined with the secondary air and burned. The primary air isn't pre-heated and actually cools the firebox. The secondary air is pre-heated and ready to burn the second it come out of the burn tubes/baffle manifold or whatever your stove uses. You in essence just make your EPA woodstove into a Chimea by burning with small loads and primary wide open all the time.

You start out like the one on the right and damper down to like like the pic on the left. Makes for quite a show for us former old style stove burners.

 

[Jags]

I'll keep an open mind and try it both ways.

Can anyone explain the theory behind less air/clean burn in the new stoves?

I'll throw a theory out for ya (and maybe we can get Corie the engineer wizard to confirm).

Newer epa stoves are as much as a "gas" burner as the old stoves were a "wood" burner (yes, I know that it is the "gas" that burns, but play along).

By "gas" burner, I am referring to the "out gassing" of the wood or pyrolysis. I believe that the out gassing can actually be advanced by having a high temp at wood level, with a reduced oxygen saturation point. The gases rise to the "reburner" (tubes or cat) where additional oxygen is introduced to the superheated reburner and bingo - almost complete combustion. Particulate matter, gases and all, yielding a cleaner burn than if oxygen alone was introduced at the burning point of the wood.

If nothing else, it sounds good.

EDIT: and BroB hit some good points too.

 

[thechimneysweep]

Hi Gerry,

[edit] Wow, SEVERAL posts happened while I was working the keyboard with these old fingers, most of them doing a better job of explaining the new EPA stoves than I did. Oh well, here it is anyway:

Your old stove had one shot at burning the particulates and gaseous volatiles contained in your load: anything not burned by the primary fire was carried up the chimney to be deposited on the inner walls via condensation as the exhaust cooled.

If typical, your old stove had a draft control that could be closed nearly all the way, starving the fire for air. The air-starved fire would smolder along with no flames, producing vast volumes of unburned particulates and volatiles, which resulted in a heavy coating of creosote in the chimney.

So, your advice to burn with the draft control wide open (or at least not closed down to smolder range) was spot on - for your old stove and other stoves of that vintage.

Today's EPA approved woodstoves are designed to have two shots at burning the particulates and volatiles. There is actually a second fire inside the firebox, which uses the exhaust from the primary fire for fuel. The secondary fire gets its own air supply, independent from the primary draft control. No matter how low you turn the primary draft control, the secondary fire gets all the air it needs to burn up the exhaust. All you have to do is wait 20-30 minutes or so after you add your fresh load for the secondary fire to flame on, and you can turn your draft control down as far as you want to prolong your burn.

The old-school wisdom about leaving the draft control wide open not only doesn't apply to today's EPA approved stoves, it is actually a bad idea. The secondary fire in your new Country will burn at 1100+ degrees, a temperature the primary fire can also approach if given unlimited combustion air. The combination of temperatures produced by both fires with a wide-open draft control can severely damage the stove, a condition manufacturers call overfiring and can cite as grounds to void your warranty.

 

[Adios Pantalones]

Load it up, heat it up, choke it down. After a little bit you get that blue flame dancing along the inside roof of the stove- looks a bit like the Northern Lights... a little shiraz... bring on the cold weather

 

[Jags]

Load it up, heat it up, choke it down. After a little bit you get that blue flame dancing along the inside roof of the stove- looks a bit like the Northern Lights... a little shiraz... bring on the cold weather

I hope you know that its all you people wishing for cold weather thats bringing this crappy summer to the rest of us. >:-(

 

[BrotherBart]

I hope you know that its all you people wishing for cold weather thats bringing this crappy summer to the rest of us. >:-(

For sure. I am hoping for a tanktop Christmas. Though I must admit that I kinda look forward to this site when all of those new stoves start firing up.

 

[Adios Pantalones]

I got a crappy summer as it is. I'd rather have nice fall weather than friggin Noah's flood.

No offense, Noah.

 

[Jags]

I hope you know that its all you people wishing for cold weather thats bringing this crappy summer to the rest of us. >:-(

For sure. I am hoping for a tanktop Christmas. Though I must admit that I kinda look forward to this site when all of those new stoves start firing up.

Yeah, its kinda cute, with a bunch of grown ups running around showing off the "new toys" and complaining that the batteries died too quick. :lol: :lol:

 

[Noah]

I'm glad I'm not the only sick individual that can't wait for below 40 degree temperatures. Of course I'll be regretting that when it's 40 below 0 temperatures.

 

[Noah]

I got a crappy summer as it is. I'd rather have nice fall weather than friggin Noah's flood.

No offense, Noah.

None taken.

 

[kjklosek]

I hope you know that its all you people wishing for cold weather thats bringing this crappy summer to the rest of us. >:-(

For sure. I am hoping for a tanktop Christmas.

You probably have a good set of tank tops in your drawer already. Just need a pair of scissors.

(Just look closely at the photo)

 

[karl]

I read the first the post and I thought it was a joke until i read his follow up post.

If you just bought new EPA stove, you definately don't want to burn it like you think you do.

 

[bluefrier]

Smokinjoe, Is that an upside down underwear in that photo?

 

[kjklosek]

Smokinjoe, Is that an upside down underwear in that photo?

Yep.

It's a redneck tanktop.

And testimony to the idea that the truth really is stranger than fiction.

J.P.

PS. Are you feeling inspired?

 

[Redox]

I'm not sure this is on topic, but I think I would burn the paint off my stove if I kept the air control wide open. Anywhere from 1/4 to 3/4 seems to work the best, depending on how fast I want it to burn. I haven't had the nerve to open'er up all the way...

Chris