Figured out why I had a chimney fire

[emt1581]

A few weeks back I had a chimney fire. I swept it and found a pretty big blockage in the cap which basically started spewing flaming bits of creosote on to some leaves on the ground and set them on fire. I ran out with the extinguisher and put it out.

But for the life of me I couldn't figure out how such a thing could happen because I keep my chimney CLEAN

So tonight I was out stacking wood on my lowered patio in anticipation of the snow that is coming tonight.

Out of sheer curiosity I took a piece of oak I'd split just after Sandy. It tested at 28% so it's still got a ways to go. Then to compare it, I split a piece of the "seasoned" stuff my wood guy dropped off 2 MONTHS ago that I've been burning ever since...43%

Now this is a guy I've used for the past few years. He's always brought me good wood that I verified by testing it. This year I figured I could trust him since he'd come through so well in years past. Not sure whether to give him another shot, strangle him, etc...

What are your thoughts?? Anyone have any such experiences?

Thanks

-Emt1581

 

[ddddddden]

. . .Out of sheer curiosity I took a piece of oak I'd split just after Sandy. It tested at 28% so it's still got a ways to go. Then to compare it, I split a piece of the "seasoned" stuff my wood guy dropped off 2 MONTHS ago that I've been burning ever since...43%

Now this is a guy I've used for the past few years. He's always brought me good wood that I verified by testing it. This year I figured I could trust him since he'd come through so well in years past. Not sure whether to give him another shot, strangle him, etc...

If he's been reliable with the dry wood before, a rarity in this business, it's possible that this was an honest mistake. I'd give him a chance to make it right. . .swap the wet wood for dry wood, give you a discount on the next load of dry, etc.

 

[EatenByLimestone]

I think I'd chalk it up to experience and call it the end of a burning season unless you have some other stuff that has been sitting longer to burn. I'd start transitioning to shoulder season wood. It would be a shame to waste so much oak trying to boil off the water and heat the house. Set the oak aside for the winter of 2015 and find some faster drying wood for 2014.

I'm glad you caught your fire before it really did any damage.

Matt

 

[fire_man]

I'm surprised that if the wood was really at 43% MC you did not have other problems, like difficulty getting reloads to start, a heavy coal base, poor heat output, and sizzling wood. 43% is very poor.

 

[madison]

I think there are a few lessons to be learned:
1. Don't trust moisture meters, they are notoriously inaccurate.
2. Don't ever assume that purchased wood has been stacked and dried
3. Wood split for 5 months (Sandy) , especially oak, is not seasoned.
4. The blockage and crap at your cap was more than likely the result of your chimney fire
5. Always have an up to date fire extinguisher
6. Always be alert to the potential of fire

 

[mellow]

There is just no way to make money selling oak firewood that has been properly seasoned for 2-3 years.

If you buy "seasoned" oak expect to stack it for 2 years before burning it.

If you buy from someone who kiln dries oak that is a different.

 

[begreen]

To madison's list I would add that there is no such thing as seasoned wood bought in the fall or later.

 

[Backwoods Savage]

Right. Madison gave an excellent list.

Lesson learned should be that right now you should already have next years wood all split and stacked out in the wind so that it has time to dry. Exception: If you want to burn oak, figure 3 years in the stack before burning.

Savage's rule of thumb: Be 3 years ahead on your wood pile and that will remove over 90% of all wood burning problems. In addition, you will be much warmer and use less wood. Yes, that means you will be saving some dollars! It is better than money in the bank and you don't even have to pay interest or taxes on it.

 

[BillsWS]

Savage's rule of thumb: Be 3 years ahead on your wood pile and that will remove over 90% of all wood burning problems. In addition, you will be much warmer and use less wood. Yes, that means you will be saving some dollars! It is better than money in the bank and you don't even have to pay interest or taxes on it.

Careful Savage, any bureaucrats see this it could change in short order .

 

[Backwoods Savage]

Careful Savage, any bureaucrats see this it could change in short order .

Let's hope not!

 

[savageactor7]

Your wood may have been acceptable but a lot of chimney caps are restrictive ...so IMO the cap is the problem.

 

[Defiant]

Were you burning with or without the cat?

 

[Lumber-Jack]

I agree with everything on Madison's list except #1, I would have to say that moisture meters are incredibly accurate compared to the most common way people try to guess as the moisture content of their wood, which is by guessing.
It's true that moisture meters can be off a couple points plus or minus, but if emt1581 has been burning oak for the past 2 months that was anywhere near 45% MC and didn't notice, then I think he'd be much better off regularly using, and relying, on his moisture meter.
Sure there are people who get use to what their firewood feels like when it's well seasoned, but can they actually determine the moisture content reliably to within a few points like a moisture meter? I doubt it, the best they can do is make a ballpark guess.
We all trust and rely on measuring devices every day that are not perfectly accurate, thermometers, gas gauges, speedometers, clocks, etc, and we know that they can be, and often are, slightly inaccurate, but the fact is we also know they can measure their respective things better than we can guess, so why is it some people feel moisture meters need to be perfectly accurate to be useful? I don't get it?

 

[danham]

I agree with both those who say MMs are acurate, and inaccurate. Schizophrenia? No, just definitions.

If I stick my MM's probles into the end of a log it wll acccurately measure the moisture content. But using that to predict how the log will burn would be grossly inaccurate.

But even beyond user error, these meters cannot always do a good job of predicting how wood will behave in your stove. There are a lot of variables, ranging from how/when it was split to ambient temp to depth opf probe insertion, that can result in an accurate reading that for burning purposes is inaccurate.

Bottom line: the MM is a useful tool to help evaluate wood, not the only tool. And the proof is always in the burning.

-dan

 

[Ashful]

I agree with both those who say MMs are acurate, and inaccurate. Schizophrenia? No, just definitions.

If I stick my MM's probles into the end of a log it wll acccurately measure the moisture content. But using that to predict how the log will burn would be grossly inaccurate.

Actually, probing the end grain is the one way you should not use a moisture meter. This simple instruction is included in the directions of every moisture meter I have ever held.

"The surface contacting electrode can be placed with any grain orientation on the side grain of wood with little effect on the meter reading. It should not, however, be used to measure MC on the end grain." - Asst. Prof. Phil Mitchell, NCSU

 

[Scols]

There is just no way to make money selling oak firewood that has been properly seasoned for 2-3 years.

If you buy "seasoned" oak expect to stack it for 2 years before burning it.

If you buy from someone who kiln dries oak that is a different.

Most wood sellers would have to charge $500+ per cord if they stacked and then seasoned their wood for 2 years +. Personally, I think that most wood sellers really believe that the wood they have piled on the lot for 6 months to a year is seasoned. Ive watched a friend with a tree service take home wood from his lot that definitely wasnt dry enough with the intention of burning it at home. This is the same wood he charges the public $225 per cord for. So I guess if some one bitches to him he figures the wood burns in his own stove so the complainer must be doing something wrong. Until I found this site I thought I was doing good by staying a year ahead but ive learned that not to be true.

 

[madison]

Excuse my laziness, but here is a post with some links I made a cpl yrs ago regarding moisture meters, some of the info may be of interest to the scientific folks:
////////////////////////////////////////////////
Here are a couple of links regarding moisture meter accuracy, tips for use etc: The first pdf is the best for the science buffs (Battenkiller - you'll be digging the first link) . Jump to pg 72 for the conclusions. Note that temperature of the wood is rather important in using the both types of MM and especially the resistance type of moisture meters

http://www.vtt.fi/inf/pdf/publications/2000/P420.pdf

http://www.woodweb.com/knowledge_base/Electric_Moisture_Meters.html

(broken link removed to http://www.ces.ncsu.edu/nreos/wood/wpn/methods_moisture.htm)

 

[ddahlgren]

A MM is a tool and no we do not buy lab grade ones for 30 or 40 dollars. They give a reasonable indication rather than an absolute number. I trust my MM a lot more than my Rutland thermometer though. It is currently reading the bottom of the scale approximately 25 F or less going by the scale in a 65 degree room.. I bought two at the same time and one does not work at all. My method is to resplit a piece or two and if the inside is noticeably cold to the touch it is way too wet to burn. Your cheek works well for this test, read it here and when checked with MM it reads over 25%. The weight of a split is a good clue as well for me. If it feels heavier than expected it is probably not ready.

For next year I have a friend that is splitting me 3 cords of maple and ash for next year this weekend to mix in with what will be 2 year+ oak. Not perfect but better in my mind than wet oak.

 

[madison]

Wonder if you bought two "MM" ' s how they would compare ?

I think your cheek method might have more merit than the " MM"

 

[ddahlgren]

Wonder if you bought two "MM" ' s how they would compare ?

I think your cheek method might have more merit than the " MM"

It is a tip i learned here and works well for me to the point that when you do the split after a while you just don't much need the MM for the most part common sense takes over at least for the obvious unseasoned wood. The other thing I have learned i think is the bark is what holds the water in as that is what it did when the tree was alive. Also i think that the seasoning does not start until split and could just rot because it did not season and dry out, kind of like making 'wood jerky' LOL.

I have learned a lot here and no doubt will more though in the back of my mind i do wonder if coal is the final answer for me in the end with a very busy work schedule running a small no struggling business until the economy picks upwith a great deal of luck. The reasons being a very long burn time, do not have to season it, takes up much less space for a given btu value, the ability to turnthe stove way down or way up though not on a momentary basis as it is slow to respond, no creosote the list is long. there are downsides as well but not that many if you are a smart burner.
Dave.

 

[raybonz]

Adopt this mindset:

ALL WOOD IS GREEN UNTIL PROVEN OTHERWISE

Ray

 

[brakatak]

Hearing how difficult it is to accumulate and store "seasoned" wood... i have to wonder why so many people stick to burning wood instead of maybe going to pellets?

For me, this is my first year burning wood, and the more i read about this, the more concerned i am about being able to have a stash sitting in my yard for say 1-3 years to season.. i figured i would mostly buy wood early spring each year (March/April) and let it sit until Nov/Dec burning season. Now, i dont think that is the best method anymore.

 

[mellow]

I can fit 4 cords of wood on my city lot, I used around 2.5 cords last year, I burn a lot of Gum/Maple/Cherry for this very reason, I do not have the room to season Oak for 3 years. That is another reason I went back to a Cat insert, I can burn the not as hard wood and still get usable heat for long periods of time.

 

[blades]

Silver Maple, Ash, Slippery Elm and some others in the same density class if split small might get you by by fall. Rock maples, Hickory, Oak you are going to have to sit on for minimum 2 years. Used a lot of silver maple, box Elder, Mountain ash the first couple years.
I am splitting some Hickory right now that has been cut in rounds( 36") laying around for several years, still high moisture content in side. It will sit for the next couple years along with the Red Oak, Beech, Locust.

 

[pen]

Hearing how difficult it is to accumulate and store "seasoned" wood... i have to wonder why so many people stick to burning wood instead of maybe going to pellets?

For me, this is my first year burning wood, and the more i read about this, the more concerned i am about being able to have a stash sitting in my yard for say 1-3 years to season.. i figured i would mostly buy wood early spring each year (March/April) and let it sit until Nov/Dec burning season. Now, i dont think that is the best method anymore.

If you have a Tractor Supply near you (or similar) go talk to them NOW about reserving a pallet or two of biobricks or other man made log (think huge pellet) that you can pick up from them in the fall.

Just got a flyer in the mail last week from them about pre-ordering. Those mixed with marginal wood will give you better results (more heat and cleaner chimney) than the marginal wood alone and also in all are not priced that badly generally speaking.

pen