Any Creosote experts identify this buildup? How do I clean it?

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scooby074

Feeling the Heat
Jan 7, 2011
423
Nova Scotia
I just went and checked the flue today and I had my usual buildup. Ive heard that some creosote is more dangerous than others and Im curious if I have to worry or if perhaps Im doing something wrong. I do plan on cleaning the flue this weekend and its been about 1 month-1.5 months since the last cleaning. I try to keep flue temperatures "In the white" on my thermometer, approx 300-450. Im burning mixed hardwood, mostly maple. Some cut this year, and some CSS for 1yr.

In my flue, there is two distinct types of creosote and they happen in two different types of stove pipe.

In the upper Selkirk style pipe, I get this light brown, fluffy buildup that's easy to clean. Im not too worried about that, should I be?

IMG_4459.jpg


The lower, single wall pipe is where I get concerned. The buildup is hard, shiny and black. Tiere is also considerable flaking where the creosote comes off in large (1"x1") sheets. The cleanout cap is regularly filled to the top edge with these flakes when it's cleaning time.

Flaking:
IMG_4458.jpg


FLakes in cleanout cap after dumping out the loose stuff:
IMG_4461.jpg


Hard, black buildup (in foreground) in single wall T leading into selkirk.
IMG_4457.jpg


Looking down into the 90* that leads to the stove. Notice flaking. Also hard black creosote
IMG_4463.jpg


Looking into T. 90* to stove is on bottom. Top of T going to selkirk is on top. Area is full of shiny hard creosote, although the picture does not show the shine very well.

IMG_4466.jpg


When I clean the stove with my Sooteater, all the brown fluffy stuff and any loose flakes are easily removed, however I cant get the hard black shiny stuff off. Im concerned that by leaving the shiny stuff behind, it's promoting more and more growth of it. Even a hand held wire brush cant cut through it.

Is there a way to remove the hard stuff?How about that powder you sprinkle in the fire?

Is there any reason to be concerned over the hard stuff being left behind after cleaning other than the fact that is seems to be getting thicker and promoting more of the same?
 
I think that black is the "glaze" which is nasty stuff to have. I'm eager to hear from folks about what they think is leading to the formation. I'm quite certain that you need to get it cleaned out though in any case as from what I understand once it gets to burning it burns hot and fast.
 
If this were my stack, I would start with one of the chimney cleaning potions. This stuff is supposed to chemically react with the creosote and make it easier to sweep (read the directions). Then I would probably take a more mechanical (physical) approach with a wire sweeping brush. Get after it.

Then I would start looking at my burning practices. For a 4 to 6 week period, that is ugly.

Edit: I would highly suggest reading the article from Tom that northwinds posted. Good info.
 
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You might be ok for this year, but I would have a professional come out after the season and do a cleaning and talk about it. I don't clean my chimney for my fireplace, only for my pellet stove. I feel I'm not qualified enough to know what's ok and what's not. Also, I just don't have the right tools or know how to use them correctly.

If it were me, I would keep doing what you're doing until after the season. If it keeps you up nights, call a chminey guy and have him come out the next chance both of you have.

JS
 
I thought someone had said that the black shiny creosote comes from an air leak at the joint,, cold air cooling the flue gases..
 
I thought someone had said that the black shiny creosote comes from an air leak at the joint,, cold air cooling the flue gases..

One possible cause, Charly, but not the only reason. Read the article that Northwinds posted. It is much more eloquent that I am and it does a great job of explaining it. That Tom dude (chimney sweep) is an all right guy.;)
 
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One possible cause, Charly, but not the only reason. Read the article that Northwinds posted. It is much more eloquent that I am and it does a great job of explaining it. That Tom dude (chimney sweep) is an all right guy.;)
Good article Jags..
 
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I just went and checked the flue today and I had my usual buildup. Ive heard that some creosote is more dangerous than others and Im curious if I have to worry or if perhaps Im doing something wrong. I do plan on cleaning the flue this weekend and its been about 1 month-1.5 months since the last cleaning. I try to keep flue temperatures "In the white" on my thermometer, approx 300-450. Im burning mixed hardwood, mostly maple. Some cut this year, and some CSS for 1yr.

You are indeed doing something wrong: Your wood cut over the summer is certainly not dry; the other probably only semi-dry. A moisture meter will help you to find out whether it can be burned this winter. In addition, your flue temps seem also a bit low. I would try to find some other dry wood like pallets or lumberscraps that you can use to get the stove and flue up to temp before trying to burn any of the other wood. Of that I would only use the stuff CSS for a year and keep the rest for next winter.
 
Your wood is wet that is one of the problems the other is your burning ways.
 
It is a thin layer of creosote, but even those thin layers can be a problem. As people have stated, wet wood and air leak could be the problem. It looks like it turns mor powdery once it gets past the single wall, but that said, I agree that is a lot of buildup for 4-6 weeks worth of burning.
 
Thanks guys. I could be wrong on the last time it was cleaned. I do try for once a month, but due to xmas and that it could have been 2 months +.. still though it is a bit of buildup.

On moisture, yes this seasons wood isnt nearly as dry as Id like (or as dry as you guys on here like), but it is "ok". I have a meter and will check. I do not have an issue with controlling my fire, I can get it at 400 on the temp gauge and hold it there until im down to charcoal. So while the wood is not ideal, im not having an issue working with it.

I think part of the reason Im building glaze is my woman likes to damp the stove way down over night and through the day.. too much. She basically shuts off the damper resulting in a smoldering fire that dirties the glass. I like to keep it on "#2-#3" which keeps the glass clear and keeps the pipe temps at around 400.

Interesting on the theory of air leakage at joints, I had no idea. That could be a part too. Some of my joints arent fully seated and some are kinda loose in the female, particularly at the 90* where it goes into the T and up the stack. I had always planned on going back and re-doing the pipe including caulking the joints, but never got to it.

Is double wall pipe worth it if I dont have clearance issues?

What about seamless pipe? I have no idea how much it costs because its not available at my building supply, is it worth it? My current pipe is the stuff that has the lock seam, some of it isnt even completely round and I know that it is causing some leaks because I have what I guess is "fly ash" near those parts where the pipes arent fully seated.

I did pick up some of the creosote powder to try. It might not even be worth it if I end up redoing it in seamless pipe. I could not find any of the more heavy duty products.

One of the things that confuses me is the fact that I have NO glaze buildup in the upper chimney. You'd think that if it was wet wood, or cold smoke related, the further I got from the stove the worse it would be??
 
I just went and checked the flue today and I had my usual buildup. Ive heard that some creosote is more dangerous than others and Im curious if I have to worry or if perhaps Im doing something wrong. I do plan on cleaning the flue this weekend and its been about 1 month-1.5 months since the last cleaning. I try to keep flue temperatures "In the white" on my thermometer, approx 300-450. Im burning mixed hardwood, mostly maple. Some cut this year, and some CSS for 1yr.

In my flue, there is two distinct types of creosote and they happen in two different types of stove pipe.

In the upper Selkirk style pipe, I get this light brown, fluffy buildup that's easy to clean. Im not too worried about that, should I be?



The lower, single wall pipe is where I get concerned. The buildup is hard, shiny and black. Tiere is also considerable flaking where the creosote comes off in large (1"x1") sheets. The cleanout cap is regularly filled to the top edge with these flakes when it's cleaning time.

Flaking:


FLakes in cleanout cap after dumping out the loose stuff:


Hard, black buildup (in foreground) in single wall T leading into selkirk.


Looking down into the 90* that leads to the stove. Notice flaking. Also hard black creosote


Looking into T. 90* to stove is on bottom. Top of T going to selkirk is on top. Area is full of shiny hard creosote, although the picture does not show the shine very well.



When I clean the stove with my Sooteater, all the brown fluffy stuff and any loose flakes are easily removed, however I cant get the hard black shiny stuff off. Im concerned that by leaving the shiny stuff behind, it's promoting more and more growth of it. Even a hand held wire brush cant cut through it.

Is there a way to remove the hard stuff?How about that powder you sprinkle in the fire?

Is there any reason to be concerned over the hard stuff being left behind after cleaning other than the fact that is seems to be getting thicker and promoting more of the same?
This was in post # 3, we have been using it since our first year burning, works great.
http://chimneysaver.com/item/4-creosote-removal-products/23-acs-anti-creo-soot-liquid.html
 
You are indeed doing something wrong: Your wood cut over the summer is certainly not dry; the other probably only semi-dry. A moisture meter will help you to find out whether it can be burned this winter. In addition, your flue temps seem also a bit low. I would try to find some other dry wood like pallets or lumberscraps that you can use to get the stove and flue up to temp before trying to burn any of the other wood. Of that I would only use the stuff CSS for a year and keep the rest for next winter.

Ideally Id like to only use the older stuff, but I have to mix it in with this years in order to make it last. If I was burning it exclusively, Id probably go through it in 2 weeks.

On stove pipe temps, Im going by the magnetic thermo, the "white range" only goes from approx 300 to 475. Lately Ive been getting it up to 525 to make a bit more heat, but the woman doesnt like that.. actually she freaks out if the needle goes over the white. Then she slams the damper in to make the temp drop:eek: I tell her that is a bad thing to do. Shes starting to come around a bit but she really doesnt like it when the needle is over 500.
 
This was in post # 3, we have been using it since our first year burning, works great.
http://chimneysaver.com/item/4-creosote-removal-products/23-acs-anti-creo-soot-liquid.html

Interesting product.

However I cant find a single dealer in Canada!!! Definitely not in my province. I even checked the Toronto region!!

Is there anything from Imperial that is decent? Products from these guys are available pretty much everywhere up here:http://www.imperialgroup.ca/stove_maintenanceproducts.cfm?c=81


This is the stuff I bought tonite. Its called Co-Mate. http://www.atlcombustion.com/comate/applications/comate_in_wood_fired_furnaces It is a new product in store, but it came recommended over the Imperial "Sweep Aid" product. I understand it is an industrial product.

A better description of the product can be found in this PDF http://www.compactappliances.ca/files/files/Comate2.pdf
 
Sounds like your wife is choking the fire....that could be the cause of the buildup. Run that stove hot!
 
Sounds like your wife is choking the fire....that could be the cause of the buildup. Run that stove hot!

Yeah.. I know that there are other issues like air leaks and less than ideal wood, but I think the smoldering fires are 75% the cause. Thing is, she thinks shes doing a good thing. Its hard to fault her. She thinks that anything over white on the gauge will result in "instant flue fire" and closing the damper through the day will save wood.
 
Yeah.. I know that there are other issues like air leaks and less than ideal wood, but I think the smoldering fires are 75% the cause. Thing is, she thinks shes doing a good thing. Its hard to fault her. She thinks that anything over white on the gauge will result in "instant flue fire" and closing the damper through the day will save wood.

You need to show her that glaze and explain that the glaze is what burns to make a flue fire - if she stopped building it up then there would be nothing to burn if you did get it hot enough to ignite.

Perhaps I missed it too - where is that thermometer sitting to get these readings anyway?
 
My thermometer is about 14" up the stack.

Here's a pic
IMG_4467.jpg
 
Zap, I notice that Imperial makes a manganese based creosote remover much like anti-creo-soot that you recommend, however its not available for sale in Canada for some reason!! Maybe that's why I cant find any of the ACS products here? Perhaps the government wont allow their sale???
 
Consider a second thermometer to put on your stovetop and let us know your temps there - this may say a lot about the burn. Also, do you see much smoke out the top of the chimney when you are burning?
 
What an odd looking setup. I would recommend getting rid of the 90 and the tee, then using an offset made of two 45 degree bends with the top bend at the ceiling box. Make sure your joints fit well, no need to add sealant, cement, or tape when you properly install pipe. Improve the wood supply and you'll be all set.

I like double wall. It is stainless steel inner wall so it will last a long time plus it drafts better and is built with better craftsmanship and quality. Things line up and fit tight with the double wall sections. It does cost more though.

Before hiring somebody to clean your pipe, consider the cost of replacing it. These days, labor costs and travel costs eat up a large portion of just throwing away the item being repaired and replacing it.
 
What an odd looking setup. I would recommend getting rid of the 90 and the tee, then using an offset made of two 45 degree bends with the top bend at the ceiling box. Make sure your joints fit well, no need to add sealant, cement, or tape when you properly install pipe. Improve the wood supply and you'll be all set.

I like double wall. It is stainless steel inner wall so it will last a long time plus it drafts better and is built with better craftsmanship and quality. Things line up and fit tight with the double wall sections. It does cost more though.

Before hiring somebody to clean your pipe, consider the cost of replacing it. These days, labor costs and travel costs eat up a large portion of just throwing away the item being repaired and replacing it.

That setup was dictated by my insurance company, including the rather ugly drop down to the T. They wanted the airspace between the ceiling and any horizontal pipe.

If I re-do it, I kind of want to keep a T of some sort to act as a cleanout / inspection location. Any ideas on that?

What brands of pipe are good?
 
Consider a second thermometer to put on your stovetop and let us know your temps there - this may say a lot about the burn. Also, do you see much smoke out the top of the chimney when you are burning?

I have an IR thermometer, so I'll try and get some readings for you. Off the top of my head, I seem to recall stove top temps of about 550 last time I checked. I'll confirm.
 
Consider a second thermometer to put on your stovetop and let us know your temps there - this may say a lot about the burn. Also, do you see much smoke out the top of the chimney when you are burning?

No smoke really when I have the damper on 2-3.

STT's are around 670 with stovepipe at 430
 
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