Chimney cleaning, how clean is clean enough?

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SD Golden

New Member
Aug 1, 2018
45
South Dakota
I cleaned my stove pipe and chimney for the first time for good measure after about a month and a half of use with a sooteater. It didn't come as clean as I had hoped, but is it good enough? There was some stuck on build up that wouldn't come off even after multiple passes, the picture is looking through the horizontal class A that passes through the thimble, but the rest of the chimney looks about the same.
 

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Looks fine to me. It's the chunks and fluff that catch fire.
Not sure where you got that idea.

I cleaned my stove pipe and chimney for the first time for good measure after about a month and a half of use with a sooteater. It didn't come as clean as I had hoped, but is it good enough? There was some stuck on build up that wouldn't come off even after multiple passes, the picture is looking through the horizontal class A that passes through the thimble, but the rest of the chimney looks about the same.
It certainly isn't great but could be much worse. You need drier wood and higher temps
 
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What stove are you burning? Cleaning after a month is a good precaution for a beginner, but certainly shouldn’t be necessary.
 
A CSL or equivalent may make the remaining residue convert to a sweepable material that then could be removed. There are many such products on the market.
 
I have a blaze king Sirocco 30, I'm burning 2 year seasoned hard wood (I admittedly can't identify wood species, but it is hard wood) and about 10-15% of my wood burned is clean oak scrap from a local cabinet maker.
 
You don’t want to us csl or chimney sweeping log with a catalytic stove . The chemicals in the log will wreck the catalyst.
 
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Seems excessive for just a month and a half with 2 year seasoned wood. Burn hotter!
 
You don’t want to us csl or chimney sweeping log with a catalytic stove . The chemicals in the log will wreck the catalyst.
Good point. I dont know about cat stoves much. Can the cat be removed for a spell or no? Just long enough to burn one to convert the deposits?

CSL= Chimney sweeping log
 
I'm a firefighter and have out out a lot of chimney fires, that's where I got that idea. I wouldn't worry that buildup as far as fire danger goes.
I agree not much danger because it isn't much volume. But those chunks and fluff are not what caught fire. Glazed creosote which is what I see a little bit of in that pipe is what caught fire. And once it is burnt it turns into chunks and fluff
 
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Glazed creosote which is what I see a little bit of in that pipe is what caught fire.
Is there evidence that there was a chimney fire here?
 
Considering I had a slammer insert install for 3 years, and cleaned it every year, I can assure you that creosote will flake, fluff, chunk, even ball up, without needing to catch fire after forming. If creosote catches fire after forming, you get ash, you know, like wood does. :)
 
Is there evidence that there was a chimney fire here?
No not at all. But it was cleaned already so any burnt residue would have been removed. But i doubt that layer would be left it it had burnt.
 
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Considering I had a slammer insert install for 3 years, and cleaned it every year, I can assure you that creosote will flake, fluff, chunk, even ball up, without needing to catch fire after forming. If creosote catches fire after forming, you get ash, you know, like wood does. :)
Some times you get ash sometimes you get the black fluff. Chances are you had chimney fires with your slammer and didnt know it if you had fluff.

And btw i clean hundreds of chimneys a year. I see all forms and plenty after fires.
 
Considering I had a slammer insert install for 3 years, and cleaned it every year, I can assure you that creosote will flake, fluff, chunk, even ball up, without needing to catch fire after forming. If creosote catches fire after forming, you get ash, you know, like wood does. :)
I'm a firefighter myself, just like reading smoke; creosote / chimney ash tells a story to.
Grey / brown dust build up in the stack is the best, that means all fuel products have been burnt in the stove and you have some fly ash that has stuck onto the pipe, usually when people have this build up and clean it minimal.

Black sand - slightly cooler flue gases, almost complete combustion in the stove, higher flue temps that cool off towards the top by the cap, user usually burns season wood <20% moisture content, runs the stove at cruising temps, has a good method of burning

Shiny diamonds - This is the point that something is a miss, causes: sometimes the wood is a little wet, stove is being turned down to low, chimney is outside the building envelope facing the northside of the property being exposed to cold prevailing winds, chimney is uninsulated, cap starts getting clogged spots first.

Shiny tar - caused by low flue gases, they pretty much start condensing on the chimney pretty much right away, this is the glaze that people refer to when that say get one of those sweeping logs; no clean your chimney with a brush and change your burning habits, usually the signs of this happening is constant smoke coming out the stack all through out the burn. Wet wood is primarily the culprit, its these users that run out of wet wood, find some dry stuff and throw it into the stove with out adjust there air or burning habits that have the chimney fire.

Fluffy air puff creosote: post chimney fire - if you see this, could be a lot or a little it means you have a fire in the chimney, the aftermath looks like those small fireworks kids play with called "snakes" or it looks like cheese doodles.
 
I'm a firefighter myself, just like reading smoke; creosote / chimney ash tells a story to.
Grey / brown dust build up in the stack is the best, that means all fuel products have been burnt in the stove and you have some fly ash that has stuck onto the pipe, usually when people have this build up and clean it minimal.

Black sand - slightly cooler flue gases, almost complete combustion in the stove, higher flue temps that cool off towards the top by the cap, user usually burns season wood <20% moisture content, runs the stove at cruising temps, has a good method of burning

Shiny diamonds - This is the point that something is a miss, causes: sometimes the wood is a little wet, stove is being turned down to low, chimney is outside the building envelope facing the northside of the property being exposed to cold prevailing winds, chimney is uninsulated, cap starts getting clogged spots first.

Shiny tar - caused by low flue gases, they pretty much start condensing on the chimney pretty much right away, this is the glaze that people refer to when that say get one of those sweeping logs; no clean your chimney with a brush and change your burning habits, usually the signs of this happening is constant smoke coming out the stack all through out the burn. Wet wood is primarily the culprit, its these users that run out of wet wood, find some dry stuff and throw it into the stove with out adjust there air or burning habits that have the chimney fire.

Fluffy air puff creosote: post chimney fire - if you see this, could be a lot or a little it means you have a fire in the chimney, the aftermath looks like those small fireworks kids play with called "snakes" or it looks like cheese doodles.

I did have about 3/32" of buildup of fluffy creosote in the chimney when I first opened it. I have been burning the stove lower in attempts to not over heat and damage the catalyst, the thermometer will over shoot if I don't turn it down. I was under the (evidently false) impression that I could run a catalyst stove down lower with less concern of creosote buildup than a non cat.
 
I did have about 3/32" of buildup of fluffy creosote in the chimney when I first opened it.
Fluffy is good, cheese doodle - fluffed with a harder shell is bad (post fire) but if you have cotton ball fluff then your doing good, wood burning is inherently hard to get the perfect clean chimney, some peoples chimney stay virtually clean the whole season others need to clean twice a season, the best advice to give is to learn your setup, try to burn only the driest of wood (if that takes getting ahead on a stock pile 3 years in advance so be it, I myself have to do that) watch your system, check your cap for smoke continually coming out or for build up. I also burn a cat stove, I love the longer burn times and it works for my schedule, but I do get cap build up, that the nature of the beast, but I also know that for the majority of my burns I have little if any smoke coming out of the cap, so it is what it is, I clean my system twice a year to be on the safe side of things, remember this should be fun and relaxing.
 
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I may try to remove the cat without damaging it to burn a creosote log, then re-install it afterward.
I wouldn't bother. Just burn hotter
 
Fluffy creosote is good but if you get to much it'll burn too, least it did for me. I had maybe 1/4 inch of fluff lining my wood furnace liner one year and that caught on fire. It burned quick and scared the hell out of me cause it looked like a volcano spitting out lava on my roof. Cleaned that chimney liner out better than i could do with a brush tho, that thing shined afterwards. Any creosote makes me nervous now.
 
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Considering I had a slammer insert install for 3 years, and cleaned it every year, I can assure you that creosote will flake, fluff, chunk, even ball up, without needing to catch fire after forming. If creosote catches fire after forming, you get ash, you know, like wood does. :)

Yes, but you kind of implied that only chunks & fluff will catch fire. Which I don't think is the case. That glazey or tarry stuff will catch fire and can burn like crazy.
 
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I cleaned my stove pipe and chimney for the first time for good measure after about a month and a half of use
What was the total amount of creo that you pulled out...less than a quart, right? Was most of it at the top end of the stack? You have a thru-wall setup with much of the chimney outside, yes? Did you get the smoke smell fixed, have you been burning with the air more open?
 
What was the total amount of creo that you pulled out...less than a quart, right? Was most of it at the top end of the stack? You have a thru-wall setup with much of the chimney outside, yes? Did you get the smoke smell fixed, have you been burning with the air more open?

I would say I got a little over a half quart of creosote out of the entire chimney including the stove pipe, and yes it is a through the wall install. It did seem like the buildup was pretty even all the way through the pipe with the exception of the stove pipe itself that had very little. I have not completely solved the smoke smell, I have gotten improvement by only filling the stove half full or less and running it higher than if it were full. I spoke with a second gentleman at Blaze King who was very helpful (this guy didn't just blame the installation) and I am currently waiting on a new door gasket. He informed me that has solved most of their issues and is where they want to start.