How much wood "hissing" is tolerable? How bad is it for the chimney???

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Another possibility....Stacking too tightly. I used to stack 3 x 16" splits in a 48" crib. No room for air to circulate. 10-15% of the center line would get punked because it stayed damp in there. Now, I stack more loosely and just get more cribs.
 
Swedishchef said:
I totally understand why everyone is saying that the wood is simply NOT dry. But how the ^#%$ can it not be? Open sun and wind for 3 summers, it was c/s/s during that time AND it is in my greenhouse which acts as a KILN.

"open sun and wind" sounds like it's also exposed to rain.

Greenhouses are often humid.

When it's stacked outside, is it in single row stacks, or multiple rows stacked together?

Ken
 
It is exposed to rain. You can't have it all I guess: sun, wind and no rain. Either no sun and no rain with wind, but if you have sun, ya gotta have rain ;)

My greenhouse is not humid. I opened the bottom walls of the greenhouse to allow a crosswind. The roof acts like a magnifying glass, temps can reach 30C on a 20C day and the front door open, bottoms rolled up, the wind blows through it.

When it is outside, single row, 4 feet away from the next rown. Face of wood is towards the wind to allow wind to blow through...

From now on, bop bricks only ;) Too bad I have 3 years of wood left.
:)

Andrew
 
Swedishchef said:
It is exposed to rain. You can't have it all I guess: sun, wind and no rain. Either no sun and no rain with wind, but if you have sun, ya gotta have rain ;)

My greenhouse is not humid. I opened the bottom walls of the greenhouse to allow a crosswind. The roof acts like a magnifying glass, temps can reach 30C on a 20C day and the front door open, bottoms rolled up, the wind blows through it.

When it is outside, single row, 4 feet away from the next rown. Face of wood is towards the wind to allow wind to blow through...

From now on, bop bricks only ;) Too bad I have 3 years of wood left.
:)

Andrew

I'm with you swedischef, I have oak cut same time as this maple and if i thought anything was going to hiss because of any moisture it would have been the oak, but as it turns out its the maple, still think personally this is more to it than mere moisture, just a crazy guess
 
My maPle hisses and foams too, whereas the locust, dried in the same woodshed for the same year is just fine. Maybe maple needs 2+ years?
 
I HAVE some two year maple that hisses, its been under cover for most of that time. I think its due to our climate. After reading that post i did not have to look to see where that person lived. I think this upstate NY lower Canada area is particularly high summer relative humidity and the sun really only comes out (30% clouds or less) one day out of 8 or ten. Ten percent or less cloudy days are maybe one every twenty days or twenty five or worse. This is purely my perception, having lived here. Further, your micro climate could be even worse. I live in the foothills of the adironacks and in the summer the clounds form daily around ten am...its almost like its the moisture from the forest rising up. I did size some solar equipment once and looked at charts that showed actual solar radiation hitting the ground and my area faired worse than Seattlle WA, and i dont think that chart took in my special little micro climate. we live in a tropical rain forest that has winter. anyway, long story short..the relative humidty in our area drastically slows dry time and hitting the highest dry percentages is not possible. the foam your seeing at the end of a burning log is probably the same foam that maple syrup operators scoop off thier boiling sap. i believe teh foam is full of impurities and minerals..but Im not sure.
 
Swedishchef said:
It is exposed to rain. You can't have it all I guess: sun, wind and no rain. Either no sun and no rain with wind, but if you have sun, ya gotta have rain ;)

The sun only affects the top layer, the top layer blocks the sunlight from the rest of the pile but the rain drips down.

Sun is at an angle. If you cover the top, the sun will still get to the ends of most of the stack.

I think a cover of some sort is best, preferably one that leaves as much air get to the stack as possible. We store our wood in a carport, open on all four sides. When that gets full, I'll start putting the racks outside but I'm going to put scraps of metal roofing over them.

Bottom line, IMO, your wood is hissing because it is not properly seasoned.

Ken
 
How about a moisture reading? A moisture meter is very cheap, and it takes some of the guess work out of the equation.
 
gzecc said:
How about a moisture reading? A moisture meter is very cheap, and it takes some of the guess work out of the equation.
That's exactly what I was thinking as I was reading some of these posts in this thread.
Speculating such things as how many months the wood has been sitting, whether it's top covered or not, how humid the region is, how much sun or wind the area gets, and things like these, just to (guess) at how dry some-body's wood "might" be??? For goodness sake people, get yourself a moisture meter and be done with it. Gota be one of the cheapest wood burners tools out there next to matches, and probably the most asked and pertinent question in this forum is, "How dry is your wood?"

On the topic of wood hissing, my dry lodgepole pine makes a light hissing noise when I stick it in a hot stove, I think most wood does if you listen carefully enough. Anyway, my wood is very dry, <15% MC. I know, I have a moisture meter. ;-)
 
Hi guys

Well, after trying to figure out what was going on I decided 2 things:

1- I purchased a moisture meter. one piece I tested indicated 22% and another one indicated 18%. So I think that eliminates the "wet wood" concept.

2- I spoke with a friend who is a forestry engineer. He explained the following: when rock maple (sugar maple) dries, so does the sugar inside of it. Like we all know, "dry" wood still has 10-20% or so of moisture. He explained that as the wood heats up, the moisture is driven out (outgassing of moisture and VOCs). The moisture then re-dissolves the crystaline dried sugar as it passes through the wood until it's exit point (along with impurities as barkeatr suggested). The foam is a mixture of moisture with dissoved sugar. As he said, that's why all the other wood of the same age doesn't foam: the moisture simply comes out as water vapour and is evaporated immediately whereas the sugar maple's water is mixed with sugar.

Andrew
 
Interesting to note that the foaming comes from the last 1/4 inch or so of the wood's outer layers. I see it more with rounds than splits, so I am going to say the bark has something to do with what I see. Some very small (2 inch) rounds with over 2 years in the stacks will hiss/foam. Never for long, but they do it. May be surface rain that gets absorbed into the outer layers. My stuff is covered though, so it should not be that.
 
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