wood at about 25-30% Whats the best I can hope for?

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jstellfox

New Member
Jul 15, 2010
97
PA
1st year burning with my Englander 30. I have 1st year burner syndrome as in I don't have super dry wood. I have had most of my wood c/s/s since mid July and now have enough for next year as well....so I am officially ahead a bit now, but I do have first year burner issuses such as not super dry wood for year 1. I am sure many of you have gone through this. Since it was a very dry summer, most of my wood is anywhere from 20% up to 30%. Whats the best I can hope for with moisture contents at that level?
 
jstellfox said:
Whats the best I can hope for with moisture contents at that level?

19-29% ;-P

Pick out the dry(er) stuff, say under 25% to start the burn season. The other stuff will continue to season, but not by a heck of alot. Consider finding a neighbor/friend/relative that burns and has dry wood to trade??
 
jstellfox said:
1st year burning with my Englander 30. I have 1st year burner syndrome as in I don't have super dry wood. I have had most of my wood c/s/s since mid July and now have enough for next year as well....so I am officially ahead a bit now, but I do have first year burner issuses such as not super dry wood for year 1. I am sure many of you have gone through this. Since it was a very dry summer, most of my wood is anywhere from 20% up to 30%. Whats the best I can hope for with moisture contents at that level?
10 lbs wood = 85000 btu dry or 0% mc
20% mc= 2lbs water @ 1000btu/lb to evaporate= 85000-2000= 83000 btu
30%mc= 3lbs water @ 1000btu/lb to evaporate=85000-3000= 82000 btu
did i do that right?
 
~*~vvv~*~ said:
10 lbs wood = 85000 btu dry or 0% mc
20% mc= 2lbs water @ 1000btu/lb to evaporate= 85000-2000= 83000 btu
30%mc= 3lbs water @ 1000btu/lb to evaporate=85000-3000= 82000 btu
did i do that right?

No, because 10 pounds of wood at 20% MC actually only has 1.7 pounds of water by weight, and it only has 8.3 pounds of wood fiber. 10 pounds of wood at 30% MC only has 2.3 pounds water by weight, and 7.7 pounds of wood fiber. Also, you used the high heat value for wood rather than the low heat value. The high heat value includes the latent heat from the water formed by combustion, but with proper flue temps above 212º you never recover that... unless, of course, you use a Magic Heat. ;-P

So...

10 pounds @ 20% MC = 8.3 pounds wood fiber x 8000 BTU = 66,400 BTU - 1700 BTU lost evaporating the water = 64,700 BTU

10 pounds @ 30% MC = 7.7 x 8000 = 61,600 - 2300 = 59,300 BTU.

Of course, you will never see all that heat, because that would only occur at 100% burn efficiency, and those figures don't consider the heat lost up the flue... unless, of course, you use a Magic Heat. :shut:
 
Battenkiller said:
~*~vvv~*~ said:
10 lbs wood = 85000 btu dry or 0% mc
20% mc= 2lbs water @ 1000btu/lb to evaporate= 85000-2000= 83000 btu
30%mc= 3lbs water @ 1000btu/lb to evaporate=85000-3000= 82000 btu
did i do that right?

No, because 10 pounds of wood at 20% MC actually only has 1.7 pounds of water by weight, and it only has 8.3 pounds of wood fiber. 10 pounds of wood at 30% MC only has 2.3 pounds water by weight, and 7.7 pounds of wood fiber. Also, you used the high heat value for wood rather than the low heat value. The high heat value includes the latent heat from the water formed by combustion, but with proper flue temps above 212º you never recover that... unless, of course, you use a Magic Heat. ;-P

So...

10 pounds @ 20% MC = 8.3 pounds wood fiber x 8000 BTU = 66,400 BTU - 1700 BTU lost evaporating the water = 64,700 BTU

10 pounds @ 30% MC = 7.7 x 8000 = 61,600 - 2300 = 59,300 BTU.

Of course, you will never see all that heat, because that would only occur at 100% burn efficiency, and those figures don't consider the heat lost up the flue... unless, of course, you use a Magic Heat. :shut:
oops & thanx. so 593/647=92% = the heat value of 30% mc wood vs 20% mc wood?
 
~*~vvv~*~ said:
oops & thanx. so 593/647=92% = the heat value of 30% mc wood vs 20% mc wood?

Exactly. Except it is only true when you figure by weight. Nobody I know cares about the weight of the wood they buy. If I buy a cord of green wood in the spring and it loses half its weight to evaporation over the next six months, did I really lose anything? All of the original wood fiber is still there, all that I lost in weight is the non-burnable part.

Another way to think about it is to figure a split of wood that weighs 10 pounds at 30% MC by convention. That wood is 23% water content by weight or 2.3 pounds, and 77% wood fiber by weight, or 7.7 pounds. Now dry that wood out until it is at 20% MC and it still has 7.7 pounds of wood fiber, but only 1.66 pounds of water by weight. So the reality is that you will only lose the difference between them in water weight x 1000, or 2.3 - 1.66 = .64 x 1000 BTU = 640 BTU.

You do the percent lost on that one, I'm too tired and Lady BK is standing behind me, nibbling at my ear. :coolsmile:
 
jstellfox said:
1st year burning with my Englander 30. I have 1st year burner syndrome as in I don't have super dry wood. I have had most of my wood c/s/s since mid July and now have enough for next year as well....so I am officially ahead a bit now, but I do have first year burner issuses such as not super dry wood for year 1. I am sure many of you have gone through this. Since it was a very dry summer, most of my wood is anywhere from 20% up to 30%. Whats the best I can hope for with moisture contents at that level?

It depends on the type(s) of wood you split in July. If it's cherry or soft maple, it may be dry enough to burn easily this year. If it's Oak, forget about it!
 
why does it matter what species at this point? 30% is 30% is it not? I would assume that my wood will not season much more for this burning season...
 
jstellfox said:
why does it matter what species at this point? 30% is 30% is it not? I would assume that my wood will not season much more for this burning season...

I think it matters what the species is. If I had to burn this year and I was looking at my pile today, I'd rather have Ash w/ 30% moisture vs. oak w/ the same moisture because the Ash will get to a lower moisture content quicker. Also, regardless of the species, the "seasoning season" is not over and it will continue to season. There are some that contend wood seasons faster in winter than summer due to drier air, etc.
 
It will also mean cooler fires and more creosote hence more chimney cleaning Be safe.
Ed
 
I have a mix of Ash, Beech and Oak, all in the 20-30% range....hopefully it does continue to season. I plan to start with the ASH
 
You could split a bunch of it smaller and that stuff will be dryer sooner - no matter what type of wood it is.
 
It'll burn. I burn mostly red and white oak, when I am not burning pine. The first year with my 30-NC I was still in my cut and split in the summer and burn it that winter mode. What you will find, Battenkiller can provide analysis I just burn the stuff, is that you are going to have hot but unpredictable burns. The secondary burns out of less than dry oak can be scary stuff. And you will burn a lot more wood. First from the fact that you will anyway with a new stove and second because it has to cook off the moisture. With less than dry red oak after it cooks off the moisture all hell breaks loose in that bad boy. Has to have something to do with the lignins in the wood. So you don't get consistent burns and you stay up late a lot.

May I present 30 percent red oak in a 30-NC laid on top of a bed of hot coals, this went on for damn near an hour:
 

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Fox, while its true that July was a little too late to start, be patient, and you MIGHT be ok. I was starting to panic a little bit in mid-August when some of my oak ( split last January) was around 28-32%. I Moved some of it to a little bit more of an open area for the next 2 months, and now theyre down to 19-23%MC. Thats not 15, but WILL make for very acceptable heating.It'll still dry out a bit more in the newly built woodshed:). (Thanx for the inspiration,everyone!)Soon I hope to be 2 years ahead! This forum rocks, and thanx to everyone here. Youve all been sooooo helpful!
 
In desperate times, when we had wood not seasoned enough, we had to stack it by the stove for a couple of weeks. Not too close, though. If ya can stack it with the faces (not ends) towards the stove and maybe rotate it once, it gets NOTICEABLY lighter real soon. But there's the issue of bugs involved maybe. This does work.
 
My first year, I had the same issue (wood delivered in May, burning that year). Luckily, a lot of it was cherry, and that dries pretty fast. My wood was 16" lengths, and I split it into 2-3" pieces a few weeks ahead of my burns, and that seemed to help a lot.

If the wood is not already outside, try moving it outside now in an open, sunny and (most importantly) windy area in single rows with a tarp or cover on the top only. If it's not already split smaller, split it smaller now. All this will help. There is still a long way to go in the drying season outside.

I've also done a test at my father-in-law's house. He brings a two week supply of wood inside and stores it near his wood stove (close, but not too close). After two weeks, the remaining wood has dropped by about 5% moisture content. So bringing more inside earlier is going to help also.
 
Mix a little of the 30% with mostly dryer wood to get by. Make sure to keep an eye on the chimminy. When I was a kid we NEVER had dry wood but somehow got by. I remember to well trying to start a fire with wet wood. >:-(
 
BrotherBart said:
It'll burn. I burn mostly red and white oak, when I am not burning pine. The first year with my 30-NC I was still in my cut and split in the summer and burn it that winter mode. What you will find, Battenkiller can provide analysis I just burn the stuff, is that you are going to have hot but unpredictable burns. The secondary burns out of less than dry oak can be scary stuff. And you will burn a lot more wood. First from the fact that you will anyway with a new stove and second because it has to cook off the moisture. With less than dry red oak after it cooks off the moisture all hell breaks loose in that bad boy. Has to have something to do with the lignins in the wood. So you don't get consistent burns and you stay up late a lot.

May I present 30 percent red oak in a 30-NC laid on top of a bed of hot coals, this went on for damn near an hour:

Stick around here for awhile Bro Bart, We will help all we can.
 
jstellfox said:
why does it matter what species at this point? 30% is 30% is it not? I would assume that my wood will not season much more for this burning season...

The species matters because all wood does not dry at the same rate. Also, your wood will continue to season and hopefully you have it stacked out in the wind. Wind and time are your friends when it comes to drying wood. Sun is good too but not as good as wind so if a choice, choose wind.

I have a mix of Ash, Beech and Oak, all in the 20-30% range….hopefully it does continue to season. I plan to start with the ASH.

That is good that you plan to start with the ash as it should be your best. Save the beech until mid winter and hopefully it has dried enough by then to get you by. I'd save the oak for another year as it usually takes a minimum of 2 years for most oak to dry properly and 3 years for the red oaks.

One more thing: Be sure you check your chimney monthly all winter long. Every 6 weeks minimum. I recommend that for your first 2-3 years. By then you should be graduated to having more than one year's wood supply on hand. Try to get 2-3 years wood on hand if at all possible.
 
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