I find this to be interesting, many people on this site swear that wood needs to be super dry to work well in these newer stoves and that may be the case but in some areas of the country wood will not get much dryer than 15% or so unless you finish it off inside. The EPA stoves were tested at 20% and that is a figure you can find any where there is information about firewood on the net so what do you think about it. A lot of misconceptions I do believe and no mention of wood density in some cases but some of the claims I read are tainted IMHO.
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bogydave
Minister of Fire
tfdchief
Minister of Fire
bogydave said:
Essentially what BD said but best results gotten at lowest MC possible, <= 10%.
Wood BTUs represent too much work to be used to drive water vapor up the flue.
No artificial steps/waypoints. Doesn't matter what I believe here, but what can be borne out by test.
SolarAndWood
Minister of Fire
I have never put anything too dry in the stove and I load it to the gills every time. Not sure what MC that is but I bet it is pretty close to as dry as it gets around here stacked outside under a roof. Pretty sure that is in the mid teens.
In My NC30
20% burns ok stove gets up to about 400
15% fires right up secondaries quick to start up works on beating back the sub 20 deg temps 500-600 deg stove
10% Toasty in side even in sub zero stove cruises at 600-700 deg. Thumb nose at power company.
20% burns ok stove gets up to about 400
15% fires right up secondaries quick to start up works on beating back the sub 20 deg temps 500-600 deg stove
10% Toasty in side even in sub zero stove cruises at 600-700 deg. Thumb nose at power company.
SolarAndWood
Minister of Fire
Do you guys really get to 10% or lower? Does it get there outside where you live or are you letting it sit inside for a while before it goes in the stove?
I dont believe I can get mine to 10%, I did get some Green Ash to 13% over the summer and it worked well but that is also a less dense wood, some of my 2 and three year old Oak is 17% .
Split and stacked for 2-3 years outside 12-15% stack inside small garage for summer results in 12-10%, Always keep some inside in stove room after about a week 10% or less. That's the stuff that gives heat close to a volcano. Splits are about 4x6. I cheat as I have a large bandsaw so I square the splits up, that lets me get 8 splits in the nc30 tight packed and that will keep my home warm for close to 12 hours depending on the wood type. Right now bunch of elm and oak, with silver maple for warmer conditions. Next year will be mostly Sugar maple. I have about 10 cords of that. Cut split and stacked last year. 8 cord mostly red oak split and stacked late last summer for 13-14 winter.
Got Wood
Minister of Fire
I voted for popcorn fart dry....sounded like it would really ignite
I dont bother taking moisture content readings. The wood is stacked for a minimum of 2 years now, soon to be 3 year min. So, I dont fuss with resplitting and taking a reading. Intellectually, the lower the better.
I dont bother taking moisture content readings. The wood is stacked for a minimum of 2 years now, soon to be 3 year min. So, I dont fuss with resplitting and taking a reading. Intellectually, the lower the better.
Got Wood said:
Just for sake of argument - wood CAN be too dry. There is a reason that your owners manual states what it does for MC%. Will wood sitting outside get to this point? Doubt it.
Too dry of wood will actually cause a DIRTY burn, believe it or not. The problem is that it outgasses at a rate that the tubes/cat can't keep up with burning it all up. Then out the stack it goes. That is where people run into problems with using too much kiln dried lumber in their stoves. Overfires and smokey stacks can result.
Again - this is just for arguments sake and in no way am I confusing this with air dried cord wood.
Wood Duck
Minister of Fire
I didnt vote because I don't have a moisture meter, which means I don't know what the moisture content of my firewood is. I do know that I haven't ever found any of my wood to be too dry. I store it uncovered outside and it burns just fine, but it burns even better after some time inside.
I burn anything under 20%, and anything"thrown"into the stove over that, I knew. I have burned under 15%, and its like no other.
Backwoods Savage
Minister of Fire
Oldspark and I sort of bat this idea around from time to time. He thinks I'm silly for stacking so much wood but I say you can not knock success. It works to let the wood dry. How long that takes depends on many factors. As for the poll, I can not vote because I have no idea what moisture content our wood is but I can probably bet it is drier than most folks wood is....and it burns wonderfully.
BWS-I think you misunderstand me, I thinks it great that you have so much wood on hand, I just dont agree on how long it takes to get the wood to a moisture level that is good to burn, If in fact wood needs to be more like 15% instead of 20% then that is some what of a game changer, not a big one but noticable none the less. I can get Cherry, Green Ash, and Silver Maple all ready to burn well (middle teens) in one long summer, it just isnt going to get much if any dryer than that considering the RH of my area, I have had some wood in the garage all winter and need to check how dry that is.Backwoods Savage said:
Bottom line is I think its great you have all that wood just dont think it takes that long to dry many of the types of wood we see burned on this forum.
Backwoods Savage
Minister of Fire
I too can get wood ready to burn over the summer. However, I also find that it burns much better if left in the stack longer. Yes, I can tell a difference between 1 year, 2 year and 3 year wood.
You are correct that it is nice to have all that wood. Just think what might happen or could happen. I think of fire_chief Steve and how he got laid up. Should an injury put me down for a while or a sickness, we won't worry much about the wood supply for sure.
You are correct that it is nice to have all that wood. Just think what might happen or could happen. I think of fire_chief Steve and how he got laid up. Should an injury put me down for a while or a sickness, we won't worry much about the wood supply for sure.
Butcher
Minister of Fire
Well I am burning 3 year ash right now seeins as I went thu my red elm earlier in this so called winter and I aint likin it one bit. Stuff is like burning rolls of terlit paper. Good hot far but it sure dont last long in the stove no matter how I adjust the air. Might as well roll up newspapers and throw them in there as they would probably burn longer. Stuff is just TOO dry in my opin. I got about 8 coards of red elm that should be about 15 to 18% next year that will suit me just fine.
This really dry stuff just dont seem to hold heat overnight like some others do. But, if it makes smoke it makes heat right?
This really dry stuff just dont seem to hold heat overnight like some others do. But, if it makes smoke it makes heat right?
This is where you and I have a difference of opinion, depending on the density and the humidity in your area wood stops losing moisture at some point, with less dense wood this happens sooner and dont think 3 year old Ash (espically Green) and cherry is gonna be noticably dryer in 3 years vs 1 year.Backwoods Savage said:
Well I hear ya and agree in theory but have not run into this myself to any extent, I have had some really dry stuff gas off and burn up in a hurry but not sure how old or type of wood it was.Butcher said:
bogydave
Minister of Fire
Backwoods Savage said:
+1
I didn't think there would be much difference.
Birch, it's said, will be dry & ready to burn after one year. I've done that & yes it burns ok.
After getting that 1 year of burning I had several cords left. the next season, the wood burned so much better it was very noticeable.
Now 3 year old birch, I notice the bark starts to get loose, it burns great too.Is a better burn than the 2 year, seems to be drier, but not sure it's more heat. Birch bark lights off fast so I have to hurry even faster to load the stove with the 3 yr old stuff.
In a previous thread, we came up with a new wood seasoning term "Aging". I'm starting to believe it has merit.
If you have space, time & can get ahead on wood & season it more than 2 years, try some. Weather, location & technique play a big role too.
Don't have a MM, used a friends once & my wood was all over the place so I didn't see much need & didn't think they were very accurate.
I "know" 2 years or more & I have good dry wood that burns well, 3 year CSS seems to be better yet, but until I get as much wood a BWS Dennis, & Zap, I can't confirm I get more or better heat.
So; "season" your wood 2 years, "Age" it 1 year & give use a report if you notice any difference. I did. Just not enough of 3 year wood to confirm it.
Not sure I am buying the aging thing, the only way my 9 month old 13% Green Ash could burn any better would be to load it self into the stove. We cant forget how some people stack their wood, BWS has in in cubes and wont dry as fast as my single rows.
iceman
Minister of Fire
Battenkiller? Where are you? He did a test that showed the mc was just a general idea.. that really 20% was more like 25
I don't know if anyone remembers but mm weren't wood specific.. there was a chart that u needed to check because if it read 20% for that wood species u might have to add or subtract however many % points...
Point is in his testing ideal wood was 15-25% and it was unlikely that many get to 15% or less as most areas across the country never sustain that low of outside humidity % ..
So again if I could find it the point was most of us with our best wood outside will never get below ~18%
Unless we store indoors or a controlled environment..
Hopefully batten will chime in or someone will remember it...
For the record I try to get my wood in at least a day before and it burns great
I don't know if anyone remembers but mm weren't wood specific.. there was a chart that u needed to check because if it read 20% for that wood species u might have to add or subtract however many % points...
Point is in his testing ideal wood was 15-25% and it was unlikely that many get to 15% or less as most areas across the country never sustain that low of outside humidity % ..
So again if I could find it the point was most of us with our best wood outside will never get below ~18%
Unless we store indoors or a controlled environment..
Hopefully batten will chime in or someone will remember it...
For the record I try to get my wood in at least a day before and it burns great
Iceman - the difference was wet basis vs dry basis. Moisture meeter reads one. Wood burners care about the other.
This is one of BK many informative posts on the subject.
"There are different ways of expressing moisture content, which don’t at all have to do with the method of determining them. The EPA test loads are Douglas fir that is between 16 and 20% wet-basis. That is expressed by taking the weight of the water present and dividing it by the weight of the entire split. Your moisture meter is calibrated for Doug fir as well, but the calculations done by the chip inside of it (or the width of the scale divisions if you are using an analog meter) are done using the dry-basis method of expressing moisture content. That is expressed by taking the weight of the water and dividing it by the weight of the dry fiber that would be present in the wood after all the water has been theoretically driven out (as would be done in a 215º oven in a lab).
Naturally, you get very different numbers, and this effect grows increasing more substantial as MC rises. It’s a mathematical thing, and has nothing to do with the actual wood, which always has the same amount of water in it.
If you want a real easy way to convert dry-basis meter readings to the wet-basis used by the EPA tests, just divide the number on the meter by that same number plus 100, and you will get the correct wet-basis MC every time.
For example, the meter says the wood is 25% MC. Add 100 to 25, then divide that number (125) by the original reading. 25/125 = 20% MC wet-basis. The high end of the EPA test range… perfect for you stove.
In another case, the meter says the wood is 19% MC. Add 100 to 19, then divide that number (119) by the original reading. 19/119 = 16% MC wet-basis. The low end of the EPA test range… perfect for your stove.
As far as a definite cutoff number, I don’t believe it exists. The way you load the stove, the type of wood, the way the wood is split, the amount of coals in there, the internal stove temps, the timing and size of wood additions, the strength of your draft…. all things that can and sometimes do have a more profound effect on the burn then just MC and draft opening. For me, the theoretical cutoff is 25% MC wet-basis (33% MC on the meter). That’s 5% more water in the wood than the maximum allowable MC in the EPA test loads. Above that, you will likely have a progressively harder time burning your wood without micro-managing the stove."
"There are different ways of expressing moisture content, which don’t at all have to do with the method of determining them. The EPA test loads are Douglas fir that is between 16 and 20% wet-basis. That is expressed by taking the weight of the water present and dividing it by the weight of the entire split. Your moisture meter is calibrated for Doug fir as well, but the calculations done by the chip inside of it (or the width of the scale divisions if you are using an analog meter) are done using the dry-basis method of expressing moisture content. That is expressed by taking the weight of the water and dividing it by the weight of the dry fiber that would be present in the wood after all the water has been theoretically driven out (as would be done in a 215º oven in a lab).
Naturally, you get very different numbers, and this effect grows increasing more substantial as MC rises. It’s a mathematical thing, and has nothing to do with the actual wood, which always has the same amount of water in it.
If you want a real easy way to convert dry-basis meter readings to the wet-basis used by the EPA tests, just divide the number on the meter by that same number plus 100, and you will get the correct wet-basis MC every time.
For example, the meter says the wood is 25% MC. Add 100 to 25, then divide that number (125) by the original reading. 25/125 = 20% MC wet-basis. The high end of the EPA test range… perfect for you stove.
In another case, the meter says the wood is 19% MC. Add 100 to 19, then divide that number (119) by the original reading. 19/119 = 16% MC wet-basis. The low end of the EPA test range… perfect for your stove.
As far as a definite cutoff number, I don’t believe it exists. The way you load the stove, the type of wood, the way the wood is split, the amount of coals in there, the internal stove temps, the timing and size of wood additions, the strength of your draft…. all things that can and sometimes do have a more profound effect on the burn then just MC and draft opening. For me, the theoretical cutoff is 25% MC wet-basis (33% MC on the meter). That’s 5% more water in the wood than the maximum allowable MC in the EPA test loads. Above that, you will likely have a progressively harder time burning your wood without micro-managing the stove."
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