What is too low for moisture readings?

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Enzo's Dad

Feeling the Heat
Dec 16, 2013
340
Canton, CT
I had alot of dead ash that I took down in March and April, As a test I re-split some on the wood. My meter read 12% to 18% is this bad? I plan on burning all of that wood this winter.
 
Kind of like having "too much money" - your wood is really bad and you should probably give it away to someone who doesn't know any better. For those of you who have too much money - you can send it my way.

All kidding aside that is perfect firewood. Congrats!
 
Yeah I guess, I thought it could hit a point of being too-dry and have no BTU's
 
Thats perfect. Enjoy it over the winter, that will be some nice wood.

Low mc wood wouldn't have less btus, it just would just burn fast and give lots of heat at one time. At least that is my understanding
 
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Wood can only get to relative humidity for low MC. So it can really only get "so" dry and not beyond without the help of a controlled environment like "kiln dried" or stashed in your attic for a couple years :)
 
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Usually , anything under 20% is good to burn. Make sure you check it at the split inside, not the end. Ends will always read lower. :)
 
Wood stored outside or in a shed in Connecticut will never get too dry. If you store it in a heated, dry building for a long time it might get so dry that you have to adjust your air settings when you burn it, but I still wouldn't call that too dry, just drier than you're used to.

Modern stoves are designed for wood with a certain moisture content (I don't recall exactly what moisture content), and I guess if you had wood drier than this moisture content you could call it 'too dry' but that never happens in real life.
 
or stashed in your attic for a couple years
I had this happen to me a couple of years ago. It was near the end of winter and I had an opportunity to purchase a cord and a bit of Lodgepole Pine with a sprinkling of Aspen and Larch. The wood had been in a garage for six years and was as white as the day it was bucked! No windows and no air. The amount of snow was still heavy in the woods so I couldn't get out to drop any standing dead. I paid $75 and had to snow blow a driveway to get to it. This stuff was so dry that when it got up to temperature it would darken my glass (not common with the air wash on these stoves) and the interior would have these wispy hairs of black crud that would float around the fire box until it headed up or stuck to my chimney. It was embarrassing as it would billow black down the street and I pride myself in burning clean. After that I used it for kindling only so my opinion is that wood can be to dry. The ops wood sounds perfect, way to go!
 
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Some people burn Kiln dried wood, and that is 8 percent, so there you go
 
I had this happen to me a couple of years ago. It was near the end of winter and I had an opportunity to purchase a cord and a bit of Lodgepole Pine with a sprinkling of Aspen and Larch. The wood had been in a garage for six years and was as white as the day it was bucked! No windows and no air. The amount of snow was still heavy in the woods so I couldn't get out to drop any standing dead. I paid $75 and had to snow blow a driveway to get to it. This stuff was so dry that when it got up to temperature it would darken my glass (not common with the air wash on these stoves) and the interior would have these wispy hairs of black crud that would float around the fire box until it headed up or stuck to my chimney. It was embarrassing as it would billow black down the street and I pride myself in burning clean. After that I used it for kindling only so my opinion is that wood can be to dry. The ops wood sounds perfect, way to go!
Sounds more like it was still soaking wet internally. Just because it was stored in a garage out of the weather doesn't mean much, particularly if it was not split
 
Sounds more like it was still soaking wet internally. Just because it was stored in a garage out of the weather doesn't mean much, particularly if it was not split

I'm thinking this as well

Wood can't get so dry that it will start burning poorly (ie black smoke etc). It may get dry enough that it's difficult to control a burn because it burns so hot, but that's a good problem to have
 
I appreciated HDRock's comment about people burning kiln dried wood -- I'm planning on doing just that come December. My Builder is saving my 2x6 and 2x4 cut offs for me. Says there's a nice pile going! He also stacked my logs from the trees that got cut down to build the house. Still, I hope my kiln dried is dry enough since it is piling up outside (not that it ever rains in Oregon :eek:) .
 
Hmmpf...I was gonna pass this up without posting my diatribe but I see some confusing info, so here it goes.

Firewood cut, split, stacked in the elements can rarely get "too dry". Some environments such as a high desert might be the exception. That said:

YES - wood can be TOO DRY for your stove. Your stoves are designed around the idea that a MC of ~20% is ideal. They are designed and engineered for this. A little under or over will not make a bunch of difference.
HOWEVER - if you were to get your hands on a bunch of wood that is very low MC, say from a furniture MFG (or in my case I had a bunch that was stored in a chicken coop for years. Read: baked) it IS possible to be too dry.

Every stove MFG warns about using KD lumber for a reason. Low moisture content.

Here is the deal: Too low of MC can cause the outgassing of the wood to exceed the stoves ability to burn them. This results in a dirty burn. If the dirty gasses don't get burned, they go up the stack. This can also cause an overfire situation for your stove if sufficient control isn't there (remember - the control of the stove is designed around ~20% MC).

So in a nut shell - yes - wood can be TOO dry (hence the MFG warning of KD stuff) and YES - too dry of wood can cause a dirty burn and the possibility of an overfire. Cord wood stacked in the elements - probably not an issue.
 
Sounds more like it was still soaking wet internally. Just because it was stored in a garage out of the weather doesn't mean much, particularly if it was not split
It was bone dry, lite as a feather.
 
I had alot of dead ash that I took down in March and April, As a test I re-split some on the wood. My meter read 12% to 18% is this bad? I plan on burning all of that wood this winter.

There is no such thing as too low. Put that MM on the shelf. And leave it there.
 
Here is the deal: Too low of MC can cause the outgassing of the wood to exceed the stoves ability to burn them. This results in a dirty burn. If the dirty gasses don't get burned, they go up the stack. This can also cause an overfire situation for your stove if sufficient control isn't there (remember - the control of the stove is designed around ~20% MC).
Well said.

I have experienced too dry wood syndrome and it is just as Jags describes. If I put a big load of too dry wood in the hot stove and open up the air control so the wood burns cleanly (no smoke out the chimney), the stove heats up too much (overfire). If I close the air control to control the temperature I don't burn as cleanly (smoke comes out the chimney).

I have 3 solutions.
(1) Burn smaller loads of the dry wood at a time so I can open up the draft enough that it burns cleanly, but there isn't enough fuel in the stove to cause it to heat up too much. Obviously this solution doesn't work for long overnight burns.
(2) Mix the dry wood with wood that has higher moisture content. Great solution if you have some wood that isn't fully seasoned.
(3) Load up the stove as normal and close the air control down so the fire is controlled and the stove doesn't overfire, and then ignore the fact that there is a bit of smoke coming out the chimney. This is the easiest and most workable solution. After the initial offgassing, or outgassing as Jags calls it, the fire tends to settle down on it's own and burn cleanly anyway. Problem solved ;)
 
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I had alot of dead ash that I took down in March and April, As a test I re-split some on the wood. My meter read 12% to 18% is this bad?
My wife's rear end is too small, and my salary is too high. I wish I had your troubles. ;)

I have experienced too dry wood syndrome and it is just as Jags describes. If I put a big load of too dry wood in the hot stove and open up the air control so the wood burns cleanly (no smoke out the chimney), the stove heats up too much (overfire). If I close the air control to control the temperature I don't burn as cleanly (smoke comes out the chimney).
Simple solution: buy a catalytic stove.
 
(3) Load up the stove as normal and close the air control down so the fire is controlled and the stove doesn't overfire, and then ignore the fact that there is a bit of smoke coming out the chimney. This is the easiest and most workable solution. After the initial offgassing, or outgassing as Jags calls it, the fire tends to settle down on it's own and burn cleanly anyway. Problem solved

Question about this one... is the smoke just a concern because it could bother the neighbors or is it a concern because of creosote? It would seem that the smoke would have very little moisture in it and that this would be different from "wet wood" smoke but I'm not sure.
 
Smoke is smoke. It contains the same junk if it is a slow, lazy smoldering fire or rapid offgassing from KD lumber. There are other arguments that could be discussed such as velocity, temps etc. that have an effect on what the smoke is "doing", but smoke is still smoke. (obviously talking strictly "clean" wood).
 
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Question about this one... is the smoke just a concern because it could bother the neighbors or is it a concern because of creosote? It would seem that the smoke would have very little moisture in it and that this would be different from "wet wood" smoke but I'm not sure.
I don't get much creosote, and I generally burn much cleaner in the house stove then most of my neighbors, so the smoke isn't much of a problem either way. But I kind of think you are right, I would think the dry wood smoke would be less of a creosote problem then trying to burn wet wood, especially considering this extra smoke from the offgassing is generally something that happens when my stove and chimney are already very warm.
 
Hmmpf...I was gonna pass this up without posting my diatribe but I see some confusing info, so here it goes.

Firewood cut, split, stacked in the elements can rarely get "too dry". Some environments such as a high desert might be the exception. That said:

YES - wood can be TOO DRY for your stove. Your stoves are designed around the idea that a MC of ~20% is ideal. They are designed and engineered for this. A little under or over will not make a bunch of difference.
HOWEVER - if you were to get your hands on a bunch of wood that is very low MC, say from a furniture MFG (or in my case I had a bunch that was stored in a chicken coop for years. Read: baked) it IS possible to be too dry.

Every stove MFG warns about using KD lumber for a reason. Low moisture content.

Here is the deal: Too low of MC can cause the outgassing of the wood to exceed the stoves ability to burn them. This results in a dirty burn. If the dirty gasses don't get burned, they go up the stack. This can also cause an overfire situation for your stove if sufficient control isn't there (remember - the control of the stove is designed around ~20% MC).

So in a nut shell - yes - wood can be TOO dry (hence the MFG warning of KD stuff) and YES - too dry of wood can cause a dirty burn and the possibility of an overfire. Cord wood stacked in the elements - probably not an issue.



This is kind of what i was worried about. but, 16- 20 is where most of the wood is at. I think I will be ok.
 
This is kind of what i was worried about. but, 16- 20 is where most of the wood is at. I think I will be ok.
You will be just fine.
 
Thank the Emerald Boar Ash.... Killed all of the ash on my property. Some of the trees were standing and punky.
 
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