Interesting article "Can wood be to Dry"

[Backwoods Savage]

Why is it that many folks - particularly Americans - have a hard time believing what the scientists are telling us? I can't tell you how many times I've heard someone say global warming is a myth just because we still see sub-zero days. They (the scientists) even had to stop calling it "global warming" (which is what it really is) and start calling it "climate change" in order to get the message across. And where is that message 5 years after "An Inconvenient Truth" brought it to mass recognition? Same place the creosote issue is 33 years after some dorky science geeks took it upon themselves to actually investigate it. Were they the first "Myth Busters", perhaps? Maybe I should submit it to the show, would anyone believe it then?

If you think deeply into it, there are very clear explanations for every observation that the responders have said here, but none of them can overturn the scientific reasoning as to why they are so. This is not the only study of this sort, just the first (that I know of). I have seen at least six studies that have touched on this issue, and all of them came to the identical conclusions. Seasoned hardwood creates the most creosote per pound of dry wood fiber burned. Ironically, green pine makes the least creosote per pound of wood fiber. Wrap your heads around that concept for a bit.

The new technologies are far better equipped to handle the excessive outgassing (smoking) that putting super-dry wood on a hot coal bed will create, but nothing new in the way wood actually burns has come up since God created the first tree... and the first lightning bolt to ignite it with. There are limits to what these technologies can do. Overcome the available air supply and you have a smoking mess. Overcome the excessive smoke with air and you have a dangerous runaway stove on your hands. Modern stoves work best and at their peak overall efficiency with wood that has a water content between 16% and 20% by weight (19% MC and 25% MC on a moisture meter). Ignore this by trying to get your wood as dry as humanely possible at your own peril.

Why is it that some folks do not believe everything science prints? And what about this so-called global warming thing? Science has even quit using the term? Who knows? But one thing I do know is that recently there are also predictions by scientists that rather than more global warming, there are trends that now show that we may in fact be going the other way.

There are many theories available and no matter what one scientist says, there will be another who comes up with other data. Is one right and one wrong? After all, science never sets out to prove anything....I think. I always thought science set out to find facts only and not to prove anything.

Back to theories in wood burning. I know there are folks who have burned wood for many years....and many of them will disagree on many aspects of the process. For example, oldspark and I will leave our oak set in the stack for a different length of time....and apparently get the same results. But what works for him doesn't work for me. Does that make him wrong? Absolutely not but I won't run him down or say that either his or my word is the last say on the thing the same as I won't say that scientists are all wrong....or all right.

Personally, I've burned wood a few years now and have my own way of doing things and because of the results I get, I will continue on that line. This in no way means that I will stop learning either. One good example is one of the best things I learned on hearth.com and that is the movement of the cool air vs trying to move the warm air. I was and still am amazed in what I learned and I hope to continue learning. But I will not agree that just because some so-called scientist or some article is printed over and over that it makes it the whole truth. Tell a lie enough times and it seems to become believable. What about the Old Farmer's Almanac? Years and years of experience and the same with many old almanacs. They print articles over and over and over and some of them are downright stupid! So no, one cannot just take as fact some article that someone or some company prints.

 

[Renovation]

Why is it that many folks - particularly Americans - have a hard time believing what the scientists are telling us?

Because much of science is highly politicized and biased in both interpretation and presentation--we see the same phenomenon on this forum.

Here, and in general, people eventually see behind the curtain of authority and certainty, and realize that the pundits are themselves biased and fallible. Especially if they get defensive and emotional when someone questions them.

Science is fantastic, and one of the best things mankind ever invented. Yet to believe that science is settled, and that many of today's truths won't be tomorrow's fallacies, is short-sighted.

As you were.

EDIT: +1 Dennis, you beat me to it.

 

[oldspark]

I fly by the seat of my pants most of the time and what makes sense to me I tend to believe and if science is on my side all the better, can any one truly believe with all the crap we put into the earths atmosphere we are not in fact making changes that will effect several generations, can wood be too dry, if it can be too wet it also can be too dry. Its not just science that says so its people who manufacture wood burners and otheres who have been involved in the burning of wood for 40 years. I am not that smart but I know when wood burns up too fast, I dont see it that often to that extent but I have seen it.

 

[Battenkiller]

Yet to believe that science is settled, and that many of today's truths won't be tomorrow's fallacies, is short-sighted.

George, what is there to settle? A well-funded laboratory using the most sensitive equipment at its disposal burned thousands of pounds of wood of different moisture contents at various burn rates, collected the emissions, weighed them and published the results. This is not theory, this is data. There is nothing to settle about data. Data are facts, not theory.

You can question the interpretations and the methodology that was used, you can demand that further studies be done to see if the results are reproducible, and that's about it. Now, when six different labs come up with similar data using similar methodology, one must assume that the methodology was correct and that the results are reproducible. What every lab found was that in controlled combustion wood burning appliances, green hardwood left less measurable creosote in the flue than seasoned hardwood. Doubting the results is akin to doubting stopping distances in car safety tests. What, somebody out there thinks he can go from 70 MPH to 0 MPH inside 50 feet despite what the the test data demonstrates, so he feels free to tell the world it's OK to tailgate? Fine. It just won't be me.

Comparing these fine scientists and their equipment to the wackos behind the Farmer's Almanac is... well, I'm just not gonna say it. Cripes, Jay Shelton had a calorimeter room in his lab that was so sensitive it could detect the heat of a person entering it. Guess he just didn't know how to use it correctly.

 

[BrowningBAR]

Why is it that many folks - particularly Americans - have a hard time believing what the scientists are telling us?

Because much of science is highly politicized and biased in both interpretation and presentation--we see the same phenomenon on this forum.

Here, and in general, people eventually see behind the curtain of authority and certainty, and realize that the pundits are themselves biased and fallible. Especially if they get defensive and emotional when someone questions them.

Science is fantastic, and one of the best things mankind ever invented. Yet to believe that science is settled, and that many of today's truths won't be tomorrow's fallacies, is short-sighted.

As you were.

EDIT: +1 Dennis, you beat me to it.

Well said. I am a huge fan of science. Science is an amazing field and always evolving and changing and learning. I am not a fan of politicizing science and science is never settled.

 

[BrowningBAR]

I just get tired of hammering the same point home on thread after thread. It is also very difficult to take this stance, which seems to fly in the face of advise given by some very experienced, well-meaning, and well-respected members here, but I feel morally obligated to bring this to peoples' attention. The whole thing makes me very testy, but I have no choice if I chose to stay an active participant in these discussions. I don't think there's a person on this board who would deliberately give poor or dangerous advise, and I'm no exception. So excuse me, I did not mean to be in attack mode with my comments.

I understand what you are getting at with wood being too dry. But, how often does that happen on this forum? There might be a few threads I can think of that talk about burns getting too hot that could be because of wood that is really dry. But it doesn't happen very often. So, this doesn't seem to be a huge issue. For the most part people on here burn at a claimed 15-20% moisture/wetness/water weight/whatever. Which is in line with your recommendations.

I don't see very many people trying to get their wood ridiculously dry.

Personally, I'd rather have wood that is too dry than too wet. Burning wet wood is a pain in the ass and I hope I never have to deal with it again.

 

[Renovation]

Yet to believe that science is settled, and that many of today's truths won't be tomorrow's fallacies, is short-sighted.

George, what is there to settle?

You've changed focus, again. My answer to your original question, and whatever insight if offers, remains.

I've said my piece and there's no need to hijack this farther in public, PM me if you like. Relax and it'll all go better. You're good enough, you're smart enough, and gosh darn it, people like you.

 

[Lumber-Jack]

Interesting discussion.
I certainly don't believe everything scientists say, but after reading that article and some personal observations, I understand now how wood actually can be too dry.
Obviously not too dry to burn, but to dry too burn at maximum efficiency.

I live in a climate that is very dry and some of the wood I have reads 5% on my moisture meter. Now I know these things have a certain amount of inaccuracy, but I'm sure the wood is well below that 14% level. Anyway, I have noticed the phenomena that John is talking about in his article, where the wood produces too much smoke when placed in a very hot stove with a good bed of coals.

Here's how I see it working and what I have observed; if I was to get a good load of this dry wood going in a hot stove and was to leave my air draft open even a small amount the combustion would go nuclear, but on my stove with the draft closed fully the fire stays under control, and I'll even get good secondarys, but I'll also get smoke coming out the chimney. When I leave my stove burning like this it will continue to burn, with secondarys, and smoke coming out the chimney for some time, until some of the excess fuel is burned up and the stove cools down a bit. Once the stove cools down a bit the smoke coming out of the chimney actually clears up and it begins burning cleaner, the way it's suppose to. Actually many of my overnight fires burn like this.

This article explains why it is, even though my wood is dry and I'm getting good secondary, I'm still sometimes getting smoke coming out of my, usually very clean burning , EPA stove.
By putting the dry wood in a hot stove the dry wood out-gasses (smokes) too fast, and to quote the article, "The problem is that a firebox load of very dry wood produces far more smoke than the air supplies of stoves are designed to provide. Besides, even if you could supply enough air, you would produce an inferno that would howl in the stove and make everyone in the house nervous. Fires that intense can seriously damage the stove's innards. Wood that is very dry produces a fire that is hard to control without making a lot of smoke." So by closing the draft I starve it for air and control the combustion so it doesn't produce an inferno, I'll still get secondarys, but it's just not burning at maximum efficiency because the stove is so hot it is causing the wood to "vaporize" (smoke) excessively, which can be observed by smoke coming out of the chimney, but I can't allow any extra air (oxygen) in to burn off that smoke, or the stove would get too hot.
Now if get a load of wood, that is not quite so dry, going in the same way, I can leave the air open a bit, allowing more oxygen in, and not worry about it going inferno, because the fire is moderated by the moisture in the wood, and because I can leave the draft open a bit, it's getting the proper amount of air to burn cleanly, and, no smoke coming out of the chimney.

Thing is, what I have also observed, and the article doesn't mention, is that same dry wood can be burned properly as long as you don't stuff too much of it in a hot stove full of coals. Feed the stove just a couple small splits and open the draft a little, it will burn fast and hot (and no smoke), but because you are limiting the fuel it can't get as hot and go inferno.
Also, use that same dry wood in a cold stove as a start up fire and you can keep the air open a bit without as much concern of it going inferno. In this case the cooler stove and fire moderates the out-gassing of the dry wood.

The biggest problem I see with "wood that is too dry" is putting too much in a hot stove with a hot bed of coals, that leads to trying to control the fire by shutting the air supply and starving the fire of oxygen needed to burn cleanly. Sounds sort of like how I get long fires in my old smoke dragon stove, but of course I get no secondary burn and a lot more smoke coming out of that old smoke dragon.

Anyway, that's how I see this issue.

 

[Battenkiller]

And what about this so-called global warming thing? Science has even quit using the term?

As I said in my post:

They (the scientists) even had to stop calling it "global warming" (which is what it really is) and start calling it "climate change" in order to get the message across.

The majority of people simply lack the background to understand the data and don't see evidence of warming in their locations. In fact, many have noticed the opposite, leading them to the erroneous conclusion that the world is cooling. About the same vision an ostrich has while his head is buried in the sand. The term "climate change" is also quite accurate, but it is something that the average Joe can related to and possibly accept.

But one thing I do know is that recently there are also predictions by scientists that rather than more global warming, there are trends that now show that we may in fact be going the other way.

There are many theories available and no matter what one scientist says, there will be another who comes up with other data. Is one right and one wrong? I always thought science set out to find facts only and not to prove anything.

The whole recent GW fiasco came about not because the data was wrong, but because the GRU in England was found to be deliberately suppressing data from examination so that it couldn't be used by the skeptics to manipulate in a way that would contradict the prevailing predictions. This was a totally unconscionable thing for scientists to do, but the data itself is nothing that NOAA and GISS haven't both confirmed by similar and other methods. There is also no one credible out there disputing the rise in CO2 during the last 200 years since the Industrial Revolution, nor the data from the ice core samples in Antarctica that shows an almost perfect long-term relationship between CO2 levels and temperature. The interpretation of this data is open to debate, but nowhere have I found that the data itself it is being questioned. Finally, there isn't a scientist in his right mind who will dispute the exponential rise in CO2 levels during the last 50 years, nor will any doubt the meteorological record during that time.

You are 100% correct that science should never try to prove anything. One of the reasons I am no longer in science is because of a remark the director of my lab made to me, which was in essence, "I know I'm right, but I just can't prove it." Bad science... BK out the door. I am very sensitive to this issue, and I know for a fact that scientists sometimes fudge their data - intentionally, or just through wishful thinking. That's what peer review is all about. 100% reliable? No way, but it catches most of the BS before the studies get published.

In the case of climate change, you get all of your info from the news media (unless you subscribe to and read "Science" or "Nature"), not from the primary literature. How much truth are you really getting?

"928 peer-reviewed scientific articles on global climate change published between 1993 and 2003... either supported the human-caused global warming consensus or did not comment on it." and yet, "...a 2004 study by Max and Jules Boykoff showing 53% of articles that appeared in major US newspapers over a fourteen year period gave roughly equal attention to scientists who expressed views that global warming was caused by humans as they did to global warming skeptics, creating a false balance."

Now who's skewing the info here, and for what politicized reasons? No one with a corporate agenda, I'm certain of that. :roll:

http://en.wikipedia.org/wiki/An_Inconvenient_Truth

In the case of the creosote studies, these guys were using the same techniques that the EPA used to develop the stove testing protocols. If you doubt their results, you really need to question some stove maker doing the same thing in New Hampshire, using the same type of equipment. Data is data. Interpreting that data is a different story. In the cases I have brought up, the only way to doubt the findings is to doubt the methods used to obtain them. Again, the same methods used throughout the stove industry since well before the first EPA regs went into place.

The following is from yet another study (Georgia Forestry Commission), this one simply to determine the amount of creosote produced by burning beetle-killed pine compared to seasoned hardwood, green hardwood, and green pine. I only have this in PDF format on my computer, so I can't provide a direct link, but these screen captures effectively show both their test procedure and the results. Nothing to interpret here, this is just four air-tight stoves (who can identify them?) burning about a ton of wood over a 33-day time span. No raging fires or wide open air needed. Flue temps in all four stoves were controlled to attain flue temps between 300-350ºF throughout the course of the study. The creosote accumulation was periodically weighed, so unless they didn't even know how to use a scale, you can't really find reason to dispute the weights. Sadly for our fellow beetle-killed pine burners, in this study the beetle-killed wood produced the most creosote of all, while the green pine produced the least.

So, I guess because science can never prove anything, we should feel free to completely ignore these studies, is that the gist of what you are saying here? Continue to get our wood drier and drier until someday science finds a way to prove it is incorrect to do so.... which of course, it can't do or it wouldn't be real science, is that right? Talk about yer classic "Catch-22" situation.

Good Lord, I'm going out to cut some of that green pine I have and toss it into the stove. Someone please call the FD for me, OK? %-

 

[BrowningBAR]

So, I guess because science can never prove anything, we should feel free to completely ignore these studies, is that the gist of what you are saying here? Continue to get our wood drier and drier until someday science finds a way to prove it is incorrect to do so.... which of course, it can't do or it wouldn't be real science, is that right? Talk about yer classic "Catch-22" situation.

Good Lord, I'm going out to cut some of that green pine I have and toss it into the stove. Someone please call the FD for me, OK? %-

Agian, I don't see a lot of issues on this forum with people complaining about their wood being too dry. The vast majority of the issues are with dry wood. Some people remark about overly hot burns, which could contribute to very dry wood, but it is a rare occurrence. You seem to be arguing with yourself on this as most people on this forum shoot for 15%-20% which is in line with your comments.

And your statistics claiming that wet pine produces less creosote than certain overly-dry wood is all well and fine, but burning wet wood is a pain in the butt. I don't care if wet wood produces gold plated fairy dust. It is annoying to heat with. I am pretty sure you and every one else would rather have the issue of a fire that is too hot than a fire that simmers and does not produce much heat.

 

[DanCorcoran]

To quote myself two days ago:

"As to wood being too dry? It depends on the stove. My Shelburne manual specifically states that kiln-dried lumber is an inappropriate fuel which can overfire the stove and void the warranty. Your stove may be different. "

So the folks who engineer stoves know what they're talking about? Wood that's too dry will either overheat the stove (if you give it enough air to burn completely) or produce smoke/creosote (if you the limit the air to control the burn rate). Why did it take two days to agree with folks that do this for a living?

Let's take this is a different direction: can water be too wet to bathe in?

 

[BrowningBAR]

To quote myself two days ago:

"As to wood being too dry? It depends on the stove. My Shelburne manual specifically states that kiln-dried lumber is an inappropriate fuel which can overfire the stove and void the warranty. Your stove may be different. "

So the folks who engineer stoves know what they're talking about? Wood that's too dry will either overheat the stove (if you give it enough air to burn completely) or produce smoke/creosote (if you the limit the air to control the burn rate). Why did it take two days to agree with folks that do this for a living?

Let's take this is a different direction: can water be too wet to bathe in?

How many on this forum are using Kiln dried wood? My point is that this is not an issue. And to say certain wet pine produces less creosote then overly dry wood of a certain species is fine, but again, who here has this problem? Additionally, I would rather have wood that is too dry then wood that is too wet.

 

[DanCorcoran]

"How many on this forum are using Kiln dried wood? My point is that this is not an issue. "

My point is that this is not an issue if folks read and follow their owner's manual...so we agree. Now about the bath water...

 

[BrowningBAR]

Now about the bath water...

What's the moister meter state and does your bath tube manufacturer offer any guidelines on water wetness?

 

[Battenkiller]

You seem to be arguing with yourself on this as most people on this forum shoot for 15%-20% which is in line with your comments.

And your statistics claiming that wet pine produces less creosote than certain overly-dry wood is all well and fine, but burning wet wood is a pain in the butt. I don't care if wet wood produces gold plated fairy dust. It is annoying to heat with. I am pretty sure you and every one else would rather have the issue of a fire that is too hot than a fire that simmers and does not produce much heat.

If I'm arguing with myself, why are you and so many others contributing to this thread? The thread is asking if firewood can be too dry. Start another thread if you have nothing useful to contribute to this one.

And it ain't my data (statistics?), I'm just copying it for others to draw conclusions from if they wish. Regarding wet wood, I've burned plenty of it in the past, and have gotten huge amounts of heat from it. You have to know how to do it is all. PITA? Of course, I'm not recommending it here, nor have I ever at any time. Simmering, smoky burns and no heat output simply means you don't know how to do it right. The authors of the report that:

"The green pine, because of its high moisture content [46.14% wet-basis, 86.67% dry-basis], was difficult to start, but once an adequate bed of coals was established, an adequate fire could be maintained."

What's "an adequate fire"? Well, they were able to maintain an average flue temp of 317ºF with the stuff. That sounds like a pretty normal burn to me.


They also reported that the green pine produced creosote "of a powdery texture", while "the creosote produced by both the wet and seasoned hardwoods had a typical sticky, tar-like consistency".

Which type would you rather find in your flue pipe?


Look, this thread is all about information. If you don't thirst for information, go look at pics of somebody's wood stacks. Nothing wrong with that at all, it's both fun and inspiring. I don't expect this information to change folks over to burning green pine, nor do I want to. I think I'll stick to dry wood myself, which is what the researchers recommend as the best choice when it is available. But by examining these observed phenomena and then applying some careful consideration to their meaning, anyone can get a little clearer idea of what goes on inside the box, with the end result being maximum heating efficiency.... even using an EPA stove with dry wood.

 

[Battenkiller]

Let's take this is a different direction: can water be too wet to bathe in?

Heck, yes. I soaked for only an hour the other night and came out all wrinkled. No more wet water for me. Dry cleaning only from now on.

 

[BrowningBAR]

If I'm arguing with myself, why are you and so many others contributing to this thread? The thread is asking if firewood can be too dry. Start another thread if you have nothing useful to contribute to this one.

Look, this thread is all about information. If you don't thirst for information, go look at pics of somebody's wood stacks.

Wow. Just wow.

 

[Battenkiller]

Wow. Just wow.

Well, I did go on to say, "Nothing wrong with that at all, it’s both fun and inspiring", did I not?

 

[Battenkiller]

Interesting discussion.
I certainly don't believe everything scientists say, but after reading that article and some personal observations, I understand now how wood actually can be too dry.
Obviously not too dry to burn, but to dry too burn at maximum efficiency.

I live in a climate that is very dry and some of the wood I have reads 5% on my moisture meter. Now I know these things have a certain amount of inaccuracy, but I'm sure the wood is well below that 14% level. Anyway, I have noticed the phenomena that John is talking about in his article, where the wood produces too much smoke when placed in a very hot stove with a good bed of coals.

Here's how I see it working and what I have observed; if I was to get a good load of this dry wood going in a hot stove and was to leave my air draft open even a small amount the combustion would go nuclear, but on my stove with the draft closed fully the fire stays under control, and I'll even get good secondarys, but I'll also get smoke coming out the chimney. When I leave my stove burning like this it will continue to burn, with secondarys, and smoke coming out the chimney for some time, until some of the excess fuel is burned up and the stove cools down a bit. Once the stove cools down a bit the smoke coming out of the chimney actually clears up and it begins burning cleaner, the way it's suppose to. Actually many of my overnight fires burn like this.

This article explains why it is, even though my wood is dry and I'm getting good secondary, I'm still sometimes getting smoke coming out of my, usually very clean burning , EPA stove.
By putting the dry wood in a hot stove the dry wood out-gasses (smokes) too fast, and to quote the article, "The problem is that a firebox load of very dry wood produces far more smoke than the air supplies of stoves are designed to provide. Besides, even if you could supply enough air, you would produce an inferno that would howl in the stove and make everyone in the house nervous. Fires that intense can seriously damage the stove's innards. Wood that is very dry produces a fire that is hard to control without making a lot of smoke." So by closing the draft I starve it for air and control the combustion so it doesn't produce an inferno, I'll still get secondarys, but it's just not burning at maximum efficiency because the stove is so hot it is causing the wood to "vaporize" (smoke) excessively, which can be observed by smoke coming out of the chimney, but I can't allow any extra air (oxygen) in to burn off that smoke, or the stove would get too hot.
Now if get a load of wood, that is not quite so dry, going in the same way, I can leave the air open a bit, allowing more oxygen in, and not worry about it going inferno, because the fire is moderated by the moisture in the wood, and because I can leave the draft open a bit, it's getting the proper amount of air to burn cleanly, and, no smoke coming out of the chimney.

Thing is, what I have also observed, and the article doesn't mention, is that same dry wood can be burned properly as long as you don't stuff too much of it in a hot stove full of coals. Feed the stove just a couple small splits and open the draft a little, it will burn fast and hot (and no smoke), but because you are limiting the fuel it can't get as hot and go inferno.
Also, use that same dry wood in a cold stove as a start up fire and you can keep the air open a bit without as much concern of it going inferno. In this case the cooler stove and fire moderates the out-gassing of the dry wood.

The biggest problem I see with "wood that is too dry" is putting too much in a hot stove with a hot bed of coals, that leads to trying to control the fire by shutting the air supply and starving the fire of oxygen needed to burn cleanly. Sounds sort of like how I get long fires in my old smoke dragon stove, but of course I get no secondary burn and a lot more smoke coming out of that old smoke dragon.

Anyway, that's how I see this issue.

Wow! Thanks, CL! That sums it up better than anything I've said here. Maybe I should come up to Canada and get some lessons in communication from guys like you and Gulland. Without a doubt, you have a very firm grasp of what is really going on with wood that is too dry.

BTW, the "constant feed" method using small pieces of super-dry wood and plenty of excess air has already been perfected. It's called a pellet stove. ;-)

 

[BrowningBAR]

Wow. Just wow.

Well, I did go on to say, "Nothing wrong with that at all, it’s both fun and inspiring", did I not?

I've never spoken down to you, yet you do it continuously.

 

[Battenkiller]

Wow. Just wow.

Well, I did go on to say, "Nothing wrong with that at all, it’s both fun and inspiring", did I not?

I've never spoken down to you, yet you do it continuously.

I'm sorry. You are right, and I won't do it again. It just seems that every thread I get on you hound me about why I am posting what I am posting. It gets extremely frustrating, and I haven't noticed you doing this with others, so I end up feeling targeted by you.

Anyway, I have not been behaving properly here, and I am truly sorry. Let's not let this incident stop you from feeling free to express your opinions about what I say, OK?

 

[oldspark]

Time for a group hug. :kiss:

 

[Battenkiller]

Time for a group hug. :kiss:

It's the dang cabin fever. I want to go canoeing and catch me some brookies. The fire always feels better when I'm out where the trees are making firewood all around me.

 

[DanCorcoran]

I filled my bath tub with wood pellets, but can't seem to work up a lather.