Creosote build-up on new wood stove

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cliff88

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Nov 4, 2012
18
Just installed the nc 30 englander with double walled supervent chimney pipe. Large amount of black tar build up inside stove and in chimney and on glass within hours. Burning dry western cedar which Is at least 5 yrs old and probably 20 yrs old stored in wooden shed. Chimney is straight and outside temp is below freezing. Had the stove so hot that paint on exterior was smoking.The connection between stove
and double walled pipe is not tight. There might be air leakage there though no smoke escapes. I guess the old cedar wood is too dry? I did have it outside in the summer and washed it and allowed it to soak in rain and then returned it to shed for several months to dry again. Darn squirrels pooped all over wood.
I have a bunch of birch that was stored outside under a breathable tarp. Not sure if that will be better wood.
 
Don't wash the wood, burn the poop as well.

I am guessing that you cut too much primary air. The smoking paint was probably just paint curing, it happens with many new stoves. Do you have a stovetop or flue thermometer? If not get them, they will help us determine what is going on.
 
Just installed the nc 30 englander with double walled supervent chimney pipe. Large amount of black tar build up inside stove and in chimney and on glass within hours. Burning dry western cedar which Is at least 5 yrs old and probably 20 yrs old stored in wooden shed. Chimney is straight and outside temp is below freezing. Had the stove so hot that paint on exterior was smoking.The connection between stove
and double walled pipe is not tight. There might be air leakage there though no smoke escapes. I guess the old cedar wood is too dry? I did have it outside in the summer and washed it and allowed it to soak in rain and then returned it to shed for several months to dry again. Darn squirrels pooped all over wood.
I have a bunch of birch that was stored outside under a breathable tarp. Not sure if that will be better wood.
no such thing as too dry wood and a new stove exterior will smoke and stink the first few times until it is "seasoned". How hot are you burning? what are your temps at stove top and stove pipe?
 
I would concur- if the wood is dry, you are shutting down the primary too soon. At a minimum get a stove top thermometer....I find an IR thermometer to be more reliable.
 
Yeah if that cedar is actually dried out after its bath then you need to put smaller loads in the stove and give it some air to breathe. Cedar is the smokiest wood on the planet. The stink and smoke off the stove is normal as said above when the paint and oils from manufacturing the steel cook out.
 
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You gave the wood a bath and then put it in the shed. I would get some thermometers.
 
momma always said you gotta keep your wood clean........you just never know when you're gonna get it out! :p;lol;)
 
There is something called western red cedar that has high btu per cord and then there is something the rest of the nation calls cedar that is way less dense. Western red cedar is the stuff of legends, second and third growth is often 4 feet across. I've burned cords and cords of cedar and it is not smokey, smells nice, splits nice, and dries nicely. If properly seasoned and not recently hydrated it is a fine wood to burn. The dang trees fall over sometimes too and when they do it can be quite a haul.
 
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Don't know what cedar that is he has in Vancouver but something is for sure crapping up that firebox.
 
I have one large chunk of birch sitting on some red coals and the infrared heat gun says 300f for stove
top. I have the air completely open. The cedar is western red and it is supposed to only good for kindling.






Inspected top of chimney and lots of creosote.

creosote014_zps9e98646d.jpg






creosote013_zps5b22c2a8.jpg


creosote011_zps80e03d6f.jpg


creosote010_zps0b728674.jpg
 
NW cedar usually burns hot and fast. How tall is this chimney from stove top to the cap?

Man, you have a lot of snow. We have none. Where are you located?
 
We burn a lot of Douglas Fur the arch for our maple operation- very hot, very fast burns. The cedar should burn similarly.
 
Yes doug fir and western red burn pretty much the same with the advantage to doug fir. It's not hickory but it is better than pine or cottonwood.

That black gunk on the stack when it is cold enough for that much snow means the new stove is not being burned hot enough. Split smaller, more air, let it get up to temp. This will burn the glass clean and keep that junk from setting up on your chimney.
 
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Is it just me, or is there not much in the way of any stove pipe protruding from that roof?
What is the pipe dimension, vertically?
 
Some "overview pictures" will help trouble shoot your system.
Sizes & lengths.
Stove & stove pipe to chimney pics
Chimney above the roof line. pics

Lots of info here. Always someone ho can solve it given the info.
They helped me get squared away .

Looks like cold stack temps from low slow burns & wet wood might be part of the problem.

Keep your chimney clean ! :)
 
Piled 5 pieces of birch in stove and temperature is up past 600f. Temp gun doesnt go above 600f.
Shut off air and temp is at 500f. My chimney only extends 1 ft past roof. I need another 2 ft piece. chimney is about
14ft long straight up.I dont really see any creosote buildup lately since i stopped using the old cedar which i think
might be too dry and old. when the resins start drying up with age firewood is useless.

This huge fire is pretty hot for my small place. I wonder if I should just burn a couple pieces of wood with air
control wide open? ie small and hot fire. Im in Yale BC. I think the amount of snow is unusual. should melt
to zero next week.
 
i stopped using the old cedar which i think
might be too dry and old. when the resins start drying up with age firewood is useless.

This huge fire is pretty hot for my small place. I wonder if I should just burn a couple pieces of wood with air
control wide open?

Wood doesn't become too dry unless it turns to dust when it rots away. If it is solid, heavy, and dry it is still good stove chow. Something else is wrong with that cedar.

Smaller fires burning briskly is a good way to reduce heat output while burning cleanly in your stove. The bad news is that the fires won't last long.
 
Temperature down to 400f. Im only heating 600sq ft, 300 sq ft is closed off for now.

the following pic depicts the defective red wood and what i called birch. might be cottonwood or something.

cooton005_zps13338e22.jpg
 
Piled 5 pieces of birch in stove and temperature is up past 600f. Temp gun doesnt go above 600f.
Shut off air and temp is at 500f. My chimney only extends 1 ft past roof. I need another 2 ft piece. chimney is about
14ft long straight up.I dont really see any creosote buildup lately since i stopped using the old cedar which i think
might be too dry and old. when the resins start drying up with age firewood is useless.

This huge fire is pretty hot for my small place. I wonder if I should just burn a couple pieces of wood with air
control wide open? ie small and hot fire. Im in Yale BC. I think the amount of snow is unusual. should melt
to zero next week.

My chimney only extends 1 ft past roof."
" I need another 2 ft piece. "
+1 on that !

Sounds as if you got it figured out.
Over 90% of the time, burn problems come back to the wood ;)

Birch is my "firewood of choice" here.
2 years seasoned & dry it burns great in my Catalytic stove

Hope the 30 isn't too much stove. Not familiar with it.
PIA to burn small shorter fires all the time.
 
Cliff88- I know you said 2', but think about 3'-4' additional pipe length. I know it's gonna cost a bit more, and you would probably need a roof brace/support, but it would be well worth it.
I added 4', for a total rise of 17'8" approx, and it's definitely been a benefit.
*If you don't want that old, nasty cedar- send it my way. I'll burn it.;)
 
Wood doesn't become too dry unless it turns to dust when it rots away. If it is solid, heavy, and dry it is still good stove chow. Something else is wrong with that cedar.

Smaller fires burning briskly is a good way to reduce heat output while burning cleanly in your stove. The bad news is that the fires won't last long.


cant read yellow. http://www.chimneysweeponline.com/howetwd2.htm

i think it is 6th question.

Q: We moved my Aunt Alice out of the family homestead a few months ago, and found a couple of cords of alder in the woodshed that must have been there since Uncle George died ten years ago! Thinking I had a real find, I appropriated the wood and have been burning it for the past several weeks. Well, my experience has been disappointing, to say the least: short duration fires, and not much heat. Now don't tell me the problem is wet wood, because after ten years in the woodshed, this stuff is BONE dry. What gives?

lilguys.jpg
A: Sounds like Uncle George's stash has gotten too dry, a condition savvy woodburners in his day used to call "punky."


Wood that has been seasoned for 9-12 months still contains about 20-25% moisture, most of which is wood resins. These resins play an important part in the three stages of wood combustion. During Stage 1, the kindling fire warms up the fresh load of wood and any remaining water content is removed by evaporation and vaporization. As the wood reaches 500 degrees or so (Stage 2), the resins begin to break down chemically, and volatile gases are released which squirt out through the wood fiber and ignite, boosting the temperature of the fire to around 1,100 degrees and producing 50-60% of the heat value from that load of wood. As the gases burn away, the flames finally attack the wood fiber itself (Stage 3), and extract the remaining heat value through the process known as charcoaling.

If your firewood has dried to the point where it has lost its resin content, your fire will go directly from Stage 1 (warming up to combustion temperature) to Stage 3 (charcoaling), skipping Stage 2 and missing out on 50-60% of the heat (and burn time) you'd expect to get from that load of wood. Here's what the US Dept. of Energy website has to say about too-dry fuelwood:

"Some well-seasoned wood can in fact be too dry for today's airtight stoves. If you place wood that is too dry on a bed of coals, it will instantly give up its gases as smoke, wasting unburned smoke and producing creosote buildup."


this was from chimneysweeponline
 
Temperature down to 400f. Im only heating 600sq ft, 300 sq ft is closed off for now.

the following pic depicts the defective red wood and what i called birch. might be cottonwood or something.

cooton005_zps13338e22.jpg
Looks like a rack-of-ribs and a piece of kindling!:):rolleyes:
 
2f
Cliff88- I know you said 2', but think about 3'-4' additional pipe length. I know it's gonna cost a bit more, and you would probably need a roof brace/support, but it would be well worth it.
I added 4', for a total rise of 17'8" approx, and it's definitely been a benefit.
*If you don't want that old, nasty cedar- send it my way. I'll burn it.;)



2ft vs 3ft is same price but what is advantage of a longer chimney? thanks.
 
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