Firewood moisture content debate for EPA FURNACE

[andym]

There's no way my Heatmax 2 would satisfactorily burn wood at 28%. Last year my wood was 18-20% and was marginal. If the wood sizzles it's too wet. This year I've got wood in the 12-16% range. No sizzling, easier lighting, cleaner glass, much better experience. I never woulda believed the difference between 15 and 20% without seeing it myself.
That said I am certain that a computer controlled furnace like the Kuuma or Heat Commander would handle more moisture.

2 morals to this story: Even the best are wrong at times, and Don't believe everything you see on Youtube!

 

[laynes69]

I'm not going to lie, the amish cut a crap ton of dead ash for the neighbor. I didn't confirm the moisture content, however the furnace kept a hot burning fire. I would have never had those results with the old furnace.

 

[usernametaken]

That video makes no sense to me either. I guess the key to the story here is to know what works best for you based on experience with your furnace/boiler. I don't have records kept like @JRHAWK9. My memory is good enough to know that I've had multiple years on my furnace now and the drier the wood, the better though. As I said on the other forum when discussing said video... my Max Caddy likes TP as much as the hoarders did during the start of the pandemic. However, it has no taste for combustible fluids at all... LOL.

I am one of the rare folks who gets sub 10% readings too. My wood is all 2-3 years CSS but on top of that, and I do believe this is the key to my lower numbers, an entire season of wood is brought into my basement in the spring and lives there until fall when I start burning again. In the basement I have a dehumidifier running. Not for the wood but just on GP. I think that the wood continues to drop in this environment after having reached the previously mentioned equilibrium while drying outdoors.

 

[lampmfg]

I am the person in the video from Kuuma talking about wood that most of you are talking about in this thread. I speak with hundreds if not thousands each year. It's easy to misspeak once in a while. My use of the word moisture was not a good choice. I should have used the term "compounds" in wood. Moisture is usually used to mean water, and it was not my intent to speak only about water. Wood contains water, cellulose, and numerous combustible carbon-based compounds. Green wood (not yet cured) is often between 60% and 120% water (as provided by the University of Tennessee Agriculture Extension Service). But this varies significantly by wood species.

Daryl Lamppa (owner and designer of the Kuuma Vapor-Fire furnaces) is the most knowledgeable person I know when it comes to wood-burning. He's been researching and testing wood appliances for over 50 years. Daryl has several books that are, sort of, required reading before you start talking with customers about his Vapor-Fire furnaces. I will provide the sources (in the near future) I was referencing in the video. Daryl has these books at his home but will bring them in so I can share them with everyone.

I am pleased to see that so many of you have a passion for the technology involved in effectively utilizing wood as an energy source. Additional sources you may want to research are anything you can find talking about Pyrolysis of wood or materials covering the production of Bio-Char, as this process is also related to burning wood.

Sincerely,

Dale Horihan

 

[LogCabinFever]

I can confirm that the drier the better. I’ve found that wetter wood will burn longer but BTUs are nowhere near bone dry wood. I also bring in at least three weeks of wood at a time in the basement and the furnace dries it out quite a bit. My seasoned wood is only a year old and yet I’d bet that after sitting in the basement, it’ll be below 10% MC on a fresh split, especially on the ash. I’ll take some readings just for fun

 

[bholler]

120% water

Really. How would wood be 120% water. So can you tell us what moisture content you recommend?

 

[usernametaken]

I was wondering that too??

 

[stoveliker]

That means more than half

Really. How would wood be 120% water. So can you tell us what moisture content you recommend?

That is based on "dry basis", i.e. (weight wet - weight dry)/(weight dry).

If you have more than 1 lbs water per 1 lbs wood, that "dry basis" calculation will give you more than 100%, e.g. the 120% noted there.

100 % dry basis is the same as 50% wet basis (i.e. half the weight is water).

 

[bholler]

That means more than half

That is based on "dry basis", i.e. (weight wet - weight dry)/(weight dry).

If you have more than 1 lbs water per 1 lbs wood, that "dry basis" calculation will give you more than 100%, e.g. the 120% noted there.

100 % dry basis is the same as 50% wet basis (i.e. half the weight is water).

Ok but he said the wood was between 60% and 120% water.

 

[stoveliker]

Ok but he said the wood was between 60% and 120% water.

Yes, and the thing that should have been added was "dry basis". Meaning that its total weight was 30-60% consisting of water for the numbers you quote.

 

[usernametaken]

So, like "Relative Humidity"

 

[LogCabinFever]

That means more than half

That is based on "dry basis", i.e. (weight wet - weight dry)/(weight dry).

If you have more than 1 lbs water per 1 lbs wood, that "dry basis" calculation will give you more than 100%, e.g. the 120% noted there.

100 % dry basis is the same as 50% wet basis (i.e. half the weight is water).

So with that formula, your wet weight would need to be more than twice the dry weight. Not sure that seems plausible.

For example:
Say,
Wet weight= 200#
Dry weight = 100#
Dry basis = (200-100)/(100) = 1.00 = 100%

So at 120% dry basis, the bone dry wood at 100#, full green saturation would be 220#.

I know green wood is a decent amount heavier than dry wood obviously, but that seems really high, like waterlogged.

 

[stoveliker]

So with that formula, your wet weight would need to be more than twice the dry weight. Not sure that seems plausible.

For example:
Say,
Wet weight= 200#
Dry weight = 100#
Dry basis = (200-100)/(100) = 1.00 = 100%

So at 120% dry basis, the bone dry wood at 100#, full green saturation would be 220#.

I know green wood is a decent amount heavier than dry wood obviously, but that seems really high, like waterlogged.

You are correct. I have not seen that either. (Though I don't weigh my wood.)

 

[yooperdave]

Not so hard to understand

120% of a 15lb chunk of wood is 18. This means, at worst conditions, that chunk of wood weighed 33 lbs.

As I process wood and find those really heavy pieces, I'll just split them and let them sit for a few years. Oak is a good example of this. It takes years for it to dry. I stated this previously in another post using slab wood as an example. After one year of dry time, no good for burning, Same for 2nd year, but noticeably better. 3rd year could burn with door closed (epa stove) but not good enough. 4th and 5th years, Now you're talking! Works the way it should!

There was one piece of red oak I remember specifically. It was all I could do to get it into the truck even after I had split it as well as I could with a maul.

2 years later when I loaded it into the OWB at below zero temps, I was amazed at how much strength I had gained!

As @lampmfg has stated in his post above, University of Tennessee provided the numbers.

And on a footnote, Daryl Lampaa has over 50 years of testing and researching wood appliances....not including his years of wood burning. That's a lot longer than many have even been alive!

 

[usernametaken]

Dave, I don't think anyone is doubting his knowledge. I think folks have just had a different experience than what their video states.

 

[bholler]

Not so hard to understand

120% of a 15lb chunk of wood is 18. This means, at worst conditions, that chunk of wood weighed 33 lbs.

As I process wood and find those really heavy pieces, I'll just split them and let them sit for a few years. Oak is a good example of this. It takes years for it to dry. I stated this previously in another post using slab wood as an example. After one year of dry time, no good for burning, Same for 2nd year, but noticeably better. 3rd year could burn with door closed (epa stove) but not good enough. 4th and 5th years, Now you're talking! Works the way it should!

There was one piece of red oak I remember specifically. It was all I could do to get it into the truck even after I had split it as well as I could with a maul.

2 years later when I loaded it into the OWB at below zero temps, I was amazed at how much strength I had gained!

As @lampmfg has stated in his post above, University of Tennessee provided the numbers.

And on a footnote, Daryl Lampaa has over 50 years of testing and researching wood appliances....not including his years of wood burning. That's a lot longer than many have even been alive!

Respectfully I don't really care how much experience the owner of the company has in this case. The person who made the video (apparently acting as a spokesperson for lampaa mfg.) Said some things that were just wrong. Then said things again here that were worded completely wrong. His numbers may be correct. But the way he said it made the statement impossible. Wood cannot be 120% water as he stated. It can be 120% on the dryness scale.

 

[yooperdave]

Respectfully I don't really care how much experience the owner of the company has in this case.

Yeah, I and all the other members reading this gathered that....


So your beef boils down to the improper use of the english language? OK, I understand.

As you age and mellow (hopefully 😇 ) you find yourself listening and that's when the learning will begin all over. All of this is respectfully also.

But man holler, isn't there a way to get your points across without being so harsh? Just sayin.......

 

[bholler]

Yeah, I and all the other members reading this gathered that....


So your beef boils down to the improper use of the english language? OK, I understand.

As you age and mellow (hopefully 😇 ) you find yourself listening and that's when the learning will begin all over. All of this is respectfully also.

But man holler, isn't there a way to get your points across without being so harsh? Just sayin.......

I am sorry if it offends you. But when a person who is acting as a spokesperson for a company says things that are flat out incorrect it reflects very poorly upon that company. Saying wood that is dried over a year is going to be to dry to burn is wrong no matter how you look at it. Saying many other companies require wood to be below 10% is wrong. Saying wood can be 120% water is wrong.

If someone has that much trouble using the English language properly maybe they shouldn't be in the position to act as a spokesperson.


If the person making the statements was infact the owner of the company with all that experience then absolutely I would care about that experience. Just as if the person had presented the numbers from the university of Tennessee in the proper way I would absolutely respect those numbers. But that is not the case.

 

[yooperdave]

I am sorry if it offends you. But when a person who is acting as a spokesperson for a company says things that are flat out incorrect it reflects very poorly upon that company. Saying wood that is dried over a year is going to be to dry to burn is wrong no matter how you look at it. Saying many other companies require wood to be below 10% is wrong. Saying wood can be 120% water is wrong.

If someone has that much trouble using the English language properly maybe they shouldn't be in the position to act as a spokesperson.


If the person making the statements was infact the owner of the company with all that experience then absolutely I would care about that experience. Just as if the person had presented the numbers from the university of Tennessee in the proper way I would absolutely respect those numbers. But that is not the case.

 

[LogCabinFever]

What’s interesting is that both the Heat Commander and Caddy Advanced manuals say that 15-20% MC is ideal for the furnace which is very practical for 1-2 yr seasoned hardwood in NE (that I’ve found).

Also I tested a few fresh splits and I find that I’m in the 12-14% MC range for 1yr seasoned hardwood and my old Jensen loves it. That’s after 2-3 weeks of being inside and the furnace helping drying it out. The furnace has probably never seen wood below 10% MC as I don’t usually season beyond 2yrs. I could probably get more BTUs out of it at 3-4yrs but I don’t think it would be worth making room for more wood. I usually replace what I burned in the woodshed each year. Whatever wasn’t burned makes it to the next season (2yrs). Not sure how I would go about storing wood for 3-4 yrs. Guys that do that must have multiple woodsheds.

Seems like the EPA furnaces accommodate a more practical seasoning period but I can’t imagine 28% MC being ideal at all.

 

[lampmfg]

I am sorry if it offends you. But when a person who is acting as a spokesperson for a company says things that are flat out incorrect it reflects very poorly upon that company. Saying wood that is dried over a year is going to be to dry to burn is wrong no matter how you look at it. Saying many other companies require wood to be below 10% is wrong. Saying wood can be 120% water is wrong.

If someone has that much trouble using the English language properly maybe they shouldn't be in the position to act as a spokesperson.


If the person making the statements was infact the owner of the company with all that experience then absolutely I would care about that experience. Just as if the person had presented the numbers from the university of Tennessee in the proper way I would absolutely respect those numbers. But that is not the case.

Ok, Holler, I’ve been biting my tongue but have heard enough of your tone. If Dale representing my company spoke incorrectly, I apologize. With limited resources, I typically shoot our videos on a whim with no editing. Our marketplace competitors are probably at least 10x bigger with a lot more resources. We try our best to get accurate information to our customers and usually do a very good job. If you aren’t going to give the benefit of the doubt to a long-time member and sponsor, I guess I don’t know what to say. Especially when they have developed the cleanest burning and most efficient indoor wood furnace on the market (out of a small creamery) here in the US with a patented gasification design. https://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=/netahtml/PTO/search-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=10,823,424&OS=10,823,424&RS=10,823,424

I can assure you that Dale is very knowledgeable about wood burning. I listen to him nearly all day, walk people through installs and explain optimal furnace operation. Our customers appreciate his thoughtfulness and patience. He gives almost every single one of them his personal cell phone to use at any time.

I would’ve been more worried about him responding to this, but a family member of his was in a snowmobiling accident, and he had to miss some work, so this isn’t a priority. Unfortunately, I didn’t think I would need to come on here to address this ASAP, but you keep making it sound like we are idiots.

I'm sure we will follow up sometime next week. Until then, we would appreciate the benefit of the doubt, or at least try to be respectful!

 

[brenndatomu]

we would appreciate the benefit of the doubt, or at least try to be respectful!

X2...and not just in this thread. The condescending tone in almost every post gets old...fast.

 

[woodey]

Couldn't agree more. If you know the history of this company and are familiar with the quality of their products and what they have achieved it's hard to imagine anyone losing respect of them over one confusing video.

As I posted last week.^^^^

 

[bholler]

To be clear I absolutely have allot of respect for your company your products and what you have done. I never said I lost respect for your company just that it reflects upon the company poorly when incorrect information is put out in your name.

I don't doubt he is very knowledgeable as I am sure you are. (Much more than me infact) But incorrect info is still incorrect info and I felt it should be corrected. Do you not agree?

I will admit my post saying maybe he shouldn't be in a position as a spokesperson was a bit disrespectful and for that I apologize. But I will not apologize for calling out incorrect information.

 

[yooperdave]

The owner of Lampaa stoves has been using his vapor fire for almost 50 years exactly! I'll say it again, longer than most have been alive and longer than even more have been burning or working! The longest he has seasoned his firewood is two years.

Must know something, no? He firebox is the older smaller version (16" length pieces as opposed to 20-21") and the most per year he has burned is 5 cord during a unusually cold year. Otherwise, it's average of 4 cord. And not creosote buildup.

Very easy people to speak with. We should all be that way.