Heavy creosote build up

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Zombie

Member
Dec 21, 2020
90
NC
Hello everyone, this past weekend I got my new chimney installed and fired up the Grandpa Bear for the first time. From advise received here, it is a 7" duravent class A. It stands a 16', black 7" single wall inside with a 8-7 reducer at the stove outlet. I have been burning round the clock since 6 'o clock on Jan 30th. I was going to check it this Sat. but I was just coming back from the chicken coop this afternoon and happened to look up at the rain cap, not good. As luck would have it, I haven't added any wood to it today because I was going to clean it out the ashes this afternoon. I went up on the roof and got the rain cap off, it is a sticky mess. It's so bad that there are drips on my metal roof and drips on the pipe under the cap. According to the magnetic thermo I have on the stove pipe, it runs around 300 to 400. The wood being burned is red oak, holly, white oak, and cherry blossom. According to the moisture meter it is all between 18 and 25%. Can someone tell me what is going wrong here?
 
Did you measure the moisture content on a fresh re-split after it has been at room temp for 24 hrs? If not, you might have a false reading. How long has the wood been seasoned?
 
This is what'a going on. I have another 4' section of chimney pipe, but did not install as I measured and met the 10/2 rule.
 

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The red and white oak, a little less than a yr, the cherry blossom and holly about 8 months?
 
Creosote can build up very quickly when the wood is wet especially when vented to a cold outdoor chimney.
 
The pipe does not seem to have much build up in it, there is a little shiny black build up in the top section of chimney but looking up through the clean out tee with a flashlight, there doesn't appear to be much or any in the middle and lower section of the chimney.
 
The pipe does not seem to have much build up in it, there is a little shiny black build up in the top section of chimney but looking up through the clean out tee with a flashlight, there doesn't appear to be much or any in the middle and lower section of the chimney.
If you started burning on January 30 and on February 3 you have this amount of creosote, even at the top of your chimney, something is wrong.
 
The pipe does not seem to have much build up in it, there is a little shiny black build up in the top section of chimney but looking up through the clean out tee with a flashlight, there doesn't appear to be much or any in the middle and lower section of the chimney.
You are burning wood that is to wet in an old steel box stove with no secondary combustion system at all creosote buildup is a given.
 
If wet wood is to blame, that's an easy fix. I'm really hoping something is not wrong with my setup. I am going to be installing a baffle plate in Grandpa. The draft on the chimney is very good, I have not had any issue at all with smoke coming back in with the doors open, but is 16" enough? The smoke seems to want to follow my roof and come down toward the ground.
 
If wet wood is to blame, that's an easy fix. I'm really hoping something is not wrong with my setup. I am going to be installing a baffle plate in Grandpa. The draft on the chimney is very good, I have not had any issue at all with smoke coming back in with the doors open, but is 16" enough? The smoke seems to want to follow my roof and come down toward the ground.
With dry wood it will certainly be better but with that stove you are always going to have creosote buildup a baffle will probably make it worse
 
No offense but your seasoning period is nowhere near long enough. The large rounds in your stack are likely very, very wet. Couple that with a old school stove. You get a mess. Keep it clean if you are going to continue burning. Good luck.
 
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No offense taken. Thank you for the replies, I am getting some wood delivered, and I know hat this stuff was on the damp side, I didn't intend to continue running it once the seasoned wood gets delivered. The last few days were me just testing it out to get a feel for how the stove would run with this chimney setup, but man, I never expected to see this much buildup this fast. When I was younger, my dad would use a creosote log about once a month and when I would sweep, all I ever got was greyish powder. Are those type of logs ok with a class A? Forgive my ignorance I'm still learning and this site has been wonderful for that.
 
No offense taken. Thank you for the replies, I am getting some wood delivered, and I know hat this stuff was on the damp side, I didn't intend to continue running it once the seasoned wood gets delivered. The last few days were me just testing it out to get a feel for how the stove would run with this chimney setup, but man, I never expected to see this much buildup this fast. When I was younger, my dad would use a creosote log about once a month and when I would sweep, all I ever got was greyish powder. Are those type of logs ok with a class A? Forgive my ignorance I'm still learning and this site has been wonderful for that.
It is very unlikely the wood you get delivered will be any drier. Creosote logs and chemicals can help convert that glaze into something easier to clean. Just make sure you don't use any salt based ones. I don't think they are sold anymore but check
 
With dry wood it will certainly be better but with that stove you are always going to have creosote buildup a baffle will probably make it worse
From what I have been reading in the classic forum, the baffle is supposed to make it burn cleaner. @coaly has some great write ups on the subject. Are there any other things I can do to run cleaner?
 
It is very unlikely the wood you get delivered will be any drier. Creosote logs and chemicals can help convert that glaze into something easier to clean. Just make sure you don't use any salt based ones. I don't think they are sold anymore but check
I hope it is, the guy says it is ready to burn and I will be checking it when he delivers it. OK, I will make sure no salt based logs. Suggestions on a good sweep brush?
 
From what I have been reading in the classic forum, the baffle is supposed to make it burn cleaner. @coaly has some great write ups on the subject. Are there any other things I can do to run cleaner?
It wastes less heat up the chimney and can possibly create a little secondary combustion in the firebox if temps are high enough. But with wet wood you will never get there. And even then the stove will never burn clean and will only be a bit more efficient
 
I hope it is, the guy says it is ready to burn and I will be checking it when he delivers it. OK, I will make sure no salt based logs. Suggestions on a good sweep brush?
They all say that and 95% of them are lying.

I would go with a rotary cleaner like the soot eater.
 
They all say that and 95% of them are lying.

I would go with a rotary cleaner like the soot eater.
We shall see this weekend, you are probably right and it will be too wet. I just looked up the sooteater, I like that. I'll order one tonite.
 
Being more efficient was my goal, that way this stove will eat less wood and smoke less.
 
Being more efficient was my goal, that way this stove will eat less wood and smoke less.
It will eat less wood. Smoking less comes from dry wood and higher temps not a baffle
 
Other than wet wood, no one has mentioned operator error.

Are you using a flue pipe damper?
How far are you closing the air dampers overnight?
You mentioned the pipe thermometer reading 300 - 400, but is it always that hot when smoke is present?

Do you hear any sizzle or hiss? Any moisture coming out of the ends of wood?