Why we talk about burning dry wood

[Hedgerow]

You got that right...at .03" of water column for a draft speed you just can't burn wet wood hot enough to burn clean.
That's another reason we try to be involved in the sizing of it too. Too many guys have that Tim Allen/Tool Time mentality....more power or bigger is better.

Their experiences tell them that the wood burners they are used too usually don't heat what the manufacture says it will heat so they want to oversize them

...not so with a Yukon furnace. Also a smaller hotter fire is way more efficient than a large smoldering fire.

Alot of truth in that statement...:hmm3grin2orange:

 

[Wood Doctor]

Bottom Line...

Here's an extract fom Keith's post:

Note the incredible drop in heating content (BTU/Lb) as the moisture content rises. That means to me that burning green wood costs you half of your heat. Season your wood before you burn or forget it.

I tell all of my customers that I season their firewood before I deliver it (and believe me, I do). I cannot recall a complaint.

 

[Oldtimer]

Green hardwood can heat just fine if you know how to run a stove. The "modern" EPA strangulated stuff, maybe not so much.
The trick is to get a fire going real good and hot with wide open drafts then shove a chunk in the stove as soon as there's room enough for it to fit. With enough draft it will produce 90% as much heat as dry wood.
Like I said, I might have burned green wood once or twice out of necessity..

 

[046]

have never measured draft speed on my JUCA, but I suspect it's much higher than .03 WC.
once dry logs get up to operating temps, from that point on green wood burns very clean.
you can see the secondary burn right above logs as gasses get released. what you get wth JUCA is a very hot fire.

this will sound totally out of wack... but my JUCA burns green logs (24in x 12in diameter logs) cleanly and puts out the same if not more heat from green logs. not just more heat due to longer burn times, but more output in amount of BTU blown out in terms of hot air delivered. already been called a liar several times over this... but I'm pretty methodical in my measurements and didn't come to this conclusion by wacky methods or using half ass tools.

there's not much normal about a JUCA. seems it does things unconventional. when door is closed, there's a distinct raise in draft speed. it's the identical effect of having an exhaust blower on a high efficiency natural gas space heater.

here's a pic of my digital manometer and pyrometer
also have a full Bacharach Fryrite inspection setup

You got that right...at .03" of water column for a draft speed you just can't burn wet wood hot enough to burn clean.
That's another reason we try to be involved in the sizing of it too. Too many guys have that Tim Allen/Tool Time mentality....more power or bigger is better. Their experiences tell them that the wood burners they are used too usually don't heat what the manufacture says it will heat so they want to oversize them...not so with a Yukon furnace. Also a smaller hotter fire is way more efficient than a large smoldering fire.

 

[CrappieKeith]

When you talk about physics there are some things that are constant. The chart showed that with 45% moisture wood is only capable of making half the btus it is able to make totally dried.

Did you know I can make water freeze at 80 degree F?

 

[mtfallsmikey]

have never measured draft speed on my JUCA, but I suspect it's much higher than .03 WC.
once dry logs get up to operating temps, from that point on green wood burns very clean.
you can see the secondary burn right above logs as gasses get released. what you get wth JUCA is a very hot fire.

this will sound totally out of wack... but my JUCA burns green logs (24in x 12in diameter logs) cleanly and puts out the same if not more heat from green logs. not just more heat due to longer burn times, but more output in amount of BTU blown out in terms of hot air delivered. already been called a liar several times over this... but I'm pretty methodical in my measurements and didn't come to this conclusion by wacky methods or using half ass tools.

there's not much normal about a JUCA. seems it does things unconventional. when door is closed, there's a distinct raise in draft speed. it's the identical effect of having an exhaust blower on a high efficiency natural gas space heater.

here's a pic of my digital manometer and pyrometer
also have a full Bacharach Fryrite inspection setup

Cool!...Still have my Fyrite, it's 35 yrs. old or so. Have to put new juice in the CO2 tester tho.

 

[J.W Younger]

I've been heating with an OWB for over 20 yrs and can tell you the average is 7-8 seasoned and 11-12 green, based on red oak that we have the most of. For me its a no brainer, cut enough that you never run out of seasoned.

 

[Oldtimer]

When you talk about physics there are some things that are constant. The chart showed that with 45% moisture wood is only capable of making half the btus it is able to make totally dried.

Did you know I can make water freeze at 80 degree F?

Do what I said, and you'll have plenty of heat. It's a matter of "kiln drying" the green wood in on top of the burning wood below. It's not magic, it's not voodoo.

 

[gwiley]

It's hard to argue with real world results.

Most physics and chemistry issues in the real world are FAR more complex than in the lab. Application of knowledge can be a game changer. We don't live in "ideal" conditions, reality has a tendency to impose itself on our expectations

 

[Hedgerow]

It's hard to argue with real world results.

Most physics and chemistry issues in the real world are FAR more complex than in the lab. Application of knowledge can be a game changer. We don't live in "ideal" conditions, reality has a tendency to impose itself on our expectations

Yup... Nothin like a good dose of "reality" to pee in your cheerios... But boy oh boy does that dry stuff catch fire quick.

 

[mtfallsmikey]

I cut 6 cords of mostly red oak back in Feb., is sitting in the shed. Still stinks! That will be used late this winter.

 

[wampum]

Do what I said, and you'll have plenty of heat. It's a matter of "kiln drying" the green wood in on top of the burning wood below. It's not magic, it's not voodoo.

I try not to get involved in most of these threads,but I have to jump in here.If you have an outdoor boiler or furnace,I have no problem with you burning wood this way. You will just use
more wood and have more smoke,if you burn green wood. But this statement that you are kiln drying your wood as you burn it is nuts.ALL wood you burn dries as you burn it,you do not
kiln dry it. Kiln dry wood is exactly that,wood that has been dried in a kiln.Most of the moisture is gone before you burn it. To say that you are drying the wood like kiln dried wood in a
burning stove in a home is not only nuts,it is unsafe and irresponsible. The moisture released while you are "so called kiln drying it,is creating creosote".There is a huge problem with burning green wood its called chimney fires,you can burn your home down. If you have a chimney fire in your outdoor burner no big deal,it is well away from your home(or should be). I would much rather wake up to a cool or even cold home then to one on fire.I have been
married going on 38 years and have used wood as my basic fuel since then(we burned wood and coal when I was a kid,at home).Like JW said,with dry wood you use less wood.I try to keep my wood stocked ahead for at least 2 years.I can not imagine the hassle of trying to keep green and dry wood to mix and match.

Unless you shut your stove down several times during the winter,to clean your chimney,this is some very bad advice.He's right its not magic,its not voodoo,its called creosote build up
and you have a good chance of burning your home down.If you live alone,do what you want. But if you have anyone living with you this is totally irresponsible.

If you want to burn green wood that is your business,but please do not try to persuade others to do the same. Their lives and their families lives are on the line.I would ask anyone who
reads this to please season their wood as long as possible. Burning green wood is kinda like not cleaning the ice off of your sidewalk.Sooner or later you will slip up,and I do not care how
long you have been walking on the ice.

 

[Cedar-Acres]

I have to say I agree with Wampum.

The primary point made by the OP is that significant potential heat energy is lost when you burn the wood green. It doesn't matter if the wood that is actively burning is green or you put green wood on top of the fire so it can dry by the time the fire reaches it. The energy is lost through the process of vaporizing the water (Google "latent heat of evaporation") whether it be in the actively burning wood or the wood piled on top of the fire. To change the phase of the water in the firebox from the liquid stored in the wood to the vapor flowing out the chimney requires a very large amount of energy. If this takes place in the firebox it will remove a very large amount of heat energy *period*.

The secondary issue in this thread is that a small portion of this large amount of water vapor exiting through the chimney along with some of the smoke solids will condense on the comparatively cooler chimney walls, this is called creosote. Under the right conditions creosote will catch fire and burn very hot. This will overheat the chimney and anything around it causing damage to the chimney and probably causing a house fire.

Therefore, if you enjoy having to collect/cut/split/stack and otherwise handle up to twice as much firewood as necessary AND don't mind putting yourself and family at risk of severe injury or death - then by all means, go ahead and burn all your wood green. Remember, we are all playing with fire, may as well be doing it as safely as possible.

 

[Oldtimer]

I try not to get involved in most of these threads,but I have to jump in here.If you have an outdoor boiler or furnace,I have no problem with you burning wood this way. You will just use
more wood and have more smoke,if you burn green wood. But this statement that you are kiln drying your wood as you burn it is nuts.ALL wood you burn dries as you burn it,you do not
kiln dry it. Kiln dry wood is exactly that,wood that has been dried in a kiln.Most of the moisture is gone before you burn it. To say that you are drying the wood like kiln dried wood in a
burning stove in a home is not only nuts,it is unsafe and irresponsible. The moisture released while you are "so called kiln drying it,is creating creosote".There is a huge problem with burning green wood its called chimney fires,you can burn your home down. If you have a chimney fire in your outdoor burner no big deal,it is well away from your home(or should be). I would much rather wake up to a cool or even cold home then to one on fire.I have been
married going on 38 years and have used wood as my basic fuel since then(we burned wood and coal when I was a kid,at home).Like JW said,with dry wood you use less wood.I try to keep my wood stocked ahead for at least 2 years.I can not imagine the hassle of trying to keep green and dry wood to mix and match.

Unless you shut your stove down several times during the winter,to clean your chimney,this is some very bad advice.He's right its not magic,its not voodoo,its called creosote build up
and you have a good chance of burning your home down.If you live alone,do what you want. But if you have anyone living with you this is totally irresponsible.

If you want to burn green wood that is your business,but please do not try to persuade others to do the same. Their lives and their families lives are on the line.I would ask anyone who
reads this to please season their wood as long as possible. Burning green wood is kinda like not cleaning the ice off of your sidewalk.Sooner or later you will slip up,and I do not care how
long you have been walking on the ice.

Get a grip. Water vapor does not turn into creosote. The green wood put in on top of the hot fire will be dried in the extreme heat before it's burned. Creosote is made when a fire is allowed to slowy smolder. I burned nothing but green wood last year, and my chimney is fine. Cleaned the stove pipe 2 times, and it wasn't even bad. There's a reason the old timers always had a hot fire going; Less creosote.
You can build a dangerous amount of creosote with bone dry wood too if you don't burn it hot enough.
And last, I am not trying to convince anyone to do anything. Just sharing 40 years of keeping a fire going, lots of times with green wood.

 

[046]

have already been called a liar multiple times when I make the claim that my JUCA has the ability to burn green wood cleanly. while putting off the same if not more heat due to longer burn times.

yours is the nicest way I've ever been called a liar... from what I can tell, what happening is as green wood is getting heated by hot logs below. wood gas is released and burns about a foot above the green logs.

note JUCA burns wide open all the time, no shutting down dampers. there's two ways to lengthen burn times on a JUCA. one is burn large chunks of wood in rounds. the other is green wood. the best is 24in x 12in diameter green oak rounds. burn chamber is massive 12cubic ft and easily holds 3-4 24in x 12in logs.

When you talk about physics there are some things that are constant. The chart showed that with 45% moisture wood is only capable of making half the btus it is able to make totally dried.

Did you know I can make water freeze at 80 degree F?

posted pic's of my tools is so folks know I'm using pro grade instruments to arrive my conclusion.

Cool!...Still have my Fyrite, it's 35 yrs. old or so. Have to put new juice in the CO2 tester tho.

you must also have a HOT fire to successfully burn green wood without creosoting up your chimney.

Do what I said, and you'll have plenty of heat. It's a matter of "kiln drying" the green wood in on top of the burning wood below. It's not magic, it's not voodoo.

Get a grip. Water vapor does not turn into creosote. The green wood put in on top of the hot fire will be dried in the extreme heat before it's burned. Creosote is made when a fire is allowed to slowy smolder. I burned nothing but green wood last year, and my chimney is fine. Cleaned the stove pipe 2 times, and it wasn't even bad. There's a reason the old timers always had a hot fire going; Less creosote.
You can build a dangerous amount of creosote with bone dry wood too if you don't burn it hot enough.
And last, I am not trying to convince anyone to do anything. Just sharing 40 years of keeping a fire going, lots of times with green wood.

 

[woodbooga]

I live maybe 30 or so miles from oldtimer. Lotta folks around here burn as he does. Some folks keep a waterbucket by the woodbox to green up seasoned wood. Fill up the stove and drop in a few sticks to moisten up bone dry wood to lengthen burntimes. Lots of stoves here that aren't EPAs, but older leakier models.

I don't burn green but save my knottiest thickest pieces for banking the firebox at nighttime.

 

[Hedgerow]

Get a grip. Water vapor does not turn into creosote. The green wood put in on top of the hot fire will be dried in the extreme heat before it's burned. Creosote is made when a fire is allowed to slowy smolder. I burned nothing but green wood last year, and my chimney is fine. Cleaned the stove pipe 2 times, and it wasn't even bad. There's a reason the old timers always had a hot fire going; Less creosote.
You can build a dangerous amount of creosote with bone dry wood too if you don't burn it hot enough.
And last, I am not trying to convince anyone to do anything. Just sharing 40 years of keeping a fire going, lots of times with green wood.

Got a point there... Creosote is caused by low flue temps... Not necessarily wet wood... Although, if you can't keep a hot fire cause your wood is wet, you might have a problem... Eh..... In a world of politically correct helmet wearers, it's easy to just say using any green wood is irresponsible and throw out any creative or
resourceful use of it. I'm still on record as liking the driest stuff there is... Only because I don't need the added burn time. I know EXACTLY what old timer meant... Something tells me he knows exactly what he's doing.:msp_tongue:

 

[CrappieKeith]

I'd have to think draft speeds would have to be at max to burn green wood.

 

[Hedgerow]

I'd have to think draft speeds would have to be at max to burn green wood.

I agree... And some units may never be able to git-er-done... I think OT is burning dry wood in order to effectively use the green. It seems to be all about the unit you're burning in.

 

[wampum]

Got a point there... Creosote is caused by low flue temps... Not necessarily wet wood... Although, if you can't keep a hot fire cause your wood is wet, you might have a problem... Eh..... In a world of politically correct helmet wearers, it's easy to just say using any green wood is irresponsible and throw out any creative or
resourceful use of it. I'm still on record as liking the driest stuff there is... Only because I don't need the added burn time. I know EXACTLY what old timer meant... Something tells me he knows exactly what he's doing.:msp_tongue:

I really have been burning wood for over 40 years,I also sold and installed stoves back in the 70's and 80's. I can honestly say that I have never advised any one that it is okay to burn green wood.
I also do not know of anyone that does not cut the air back when they go to bed,stoves tend to glow red when left with the air wide open. I like to have a good bed of coals,before I load it up for the night.I believe this keeps the fire going a
lot longer,then trying to add green wood. Oldtimer claims he has to get up at 3am to reload his stove. I do not reload my stoves until 7 to 8 in the am,I would change the way I do things if I had to get up at 3am every night as he said to fix the stove. My Fisher in the basement is over 30 years old and my newer soap stone upstairs is about 8 years old.I have no trouble at all
keeping a fire in all night. My Fisher actually stays in better then the new stove.
From my experience dry wood is always better,period.You will burn less,and have better control.