Black tar in stovepipe?

Status
Not open for further replies.

hudson63

New Member
Apr 19, 2015
7
duluth mn
So I noticed this dripping from my stovepipe today. It's a very very sticky black tar leaking from the joints on my stove pipe. I know it's creosote but my question is why. I just cleaned my pipe and installed a new liner less than 2 weeks ago so everything is clean. I burn a hot fire and only use wood with 20 percent moisture or less. This only seems to happen after I burn an aluminum can or 2. So the long and short is this tar leaking a good thing or a bad thing
 

Attachments

begreen

Mooderator
Staff member
Nov 18, 2005
81,822
South Puget Sound, WA
Piping is upside down. The male (crimped) end it supposed to be pointed down toward the stove. This allows creosote to drip back toward the furnace without running down the pipe.
 

CountryBoy19

Minister of Fire
Jul 29, 2010
962
Southern IN
Piping is upside down. The male (crimped) end it supposed to be pointed down toward the stove. This allows creosote to drip back toward the furnace without running down the pipe.
This^^^ Your pipe is installed incorrectly

Some form of creosote will happen during startup. Creosote production can be increased by a number of factor including, but not limited to, non-EPA stove, non-ideal wood, poor chimney/pipe conditions, poor burning technique etc.

Is this an EPA stove? What are your flue temps? Insulated flue or non-insulated?
 

hudson63

New Member
Apr 19, 2015
7
duluth mn
Well that explains a lot....... And to answer questions epa stove no insulated flue no temp of pipe too hot to touch without burning yourself instantly. I can't believe no one else learned the can trick as a kid. Supposedly burning a can or two helps condition creosote so it turns flaky and falls off v sticky tar. No idea if it works or not but I still throw one in in addition to creosote logs and regular brushings
 

jatoxico

Minister of Fire
Aug 8, 2011
4,218
Long Island NY
Looks like you're running some kind of furnace? Does it have to idle when there's no call for heat? PS never heard of the can trick.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
20,973
central pa
Well that explains a lot....... And to answer questions epa stove no insulated flue no temp of pipe too hot to touch without burning yourself instantly. I can't believe no one else learned the can trick as a kid. Supposedly burning a can or two helps condition creosote so it turns flaky and falls off v sticky tar. No idea if it works or not but I still throw one in in addition to creosote logs and regular brushings
If you dont have temps of the pipe how do you know you are burning hot fires? If your wood really is sub 20% and your stove is an epa stove you should not be seeing that much creosote upside down or not. And btw the can thing doesn't do anything And you shouldn't need it anyway if you burn correctly
 

CountryBoy19

Minister of Fire
Jul 29, 2010
962
Southern IN
If you dont have temps of the pipe how do you know you are burning hot fires? If your wood really is sub 20% and your stove is an epa stove you should not be seeing that much creosote upside down or not. And btw the can thing doesn't do anything And you shouldn't need it anyway if you burn correctly
Don't want to insult anybody but this^^^

Fires are really hot, even a "cool fire" should have the pipe too hot to touch, so that's not an accurate measure. An EPA stove burning dry wood, operating properly should NOT be producing creosote like that. I suspect wood may be suspect; many people think their wood is dry even when it isn't. Heck, my first winter burning I thought my wood was great. I bought a moisture meter that said my wood was marginal (20-25%) and I noticed a HUGE difference in burning from year 1 to year 2 when my wood was sub 20%... it just gets better every year.
 

Hogwildz

Minister of Fire
Is the elbow S.S., looks like galv?
 

kennyp2339

Minister of Fire
Feb 16, 2014
4,706
07462
I'm suspect of that also Hog, to the op please make sure your smoke pipe is stainless steel, if its galvanized and gets to hot your poisoning yourself, gv pipe will break down, that adjustable elbow will fail. Please fix it, you got 3 types of danger going on here, regardless of burn temp or wood moisture level.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
20,973
central pa
I am sorry guys that looks like plain old black pipe that has greyed some to me and adjustable elbows are just fine in applications like that
 

firefighterjake

Minister of Fire
Jul 22, 2008
19,053
Unity/Bangor, Maine
Well that explains a lot....... And to answer questions epa stove no insulated flue no temp of pipe too hot to touch without burning yourself instantly. I can't believe no one else learned the can trick as a kid. Supposedly burning a can or two helps condition creosote so it turns flaky and falls off v sticky tar. No idea if it works or not but I still throw one in in addition to creosote logs and regular brushings
Some random thoughts . . . and just my opinions . . . I mean no disrespect . . .

* I'm a big believer in thermometers -- flue and stove top. I've often said running a woodstove without thermometers is akin to driving a car without a functioning gas gauge and engine temperature gauge -- the car will still run and may run fine or it may not be running as well as you may think. My stove top thermo helps me know when the stove is getting dangerously close to being overfired and my flue thermo lets me know when I need to start closing the air so I'm burning in the "Goldilocks Zone" -- not too cool to produce excessive creosote and not too hot to ignite whatever creosote may be in the flue.

* I thought you might be burning cans in an effort to fix the creosote. I've been here for a few years now and while I've never known anyone around here to do such a thing I have read folks in the past who have tried this . . . or potato peels . . . or some other idea. There have been some debates on whether some of these things work or not, but the overwhelming feeling comes back to this -- the best thing is to burn seasoned wood, burn at the right temps (the aforementioned Goldilocks Zone -- not too hot, not too cold, but just right) and sweep the chimney regularly (i.e. when there is a build up of say a quarter inch or more.)

* General consensus is that the chimney sweep logs do work . . . to a point . . .they can convert the sticky creosote tar into something that can be swept, but the creosote still needs to be swept as the majority will not fall to the base of the chimney. In several years of burning I have never felt the need to use a creosote log since I burn seasoned wood, sweep regularly and burn at the proper temps.
 
  • Like
Reactions: bholler

Seasoned Oak

Minister of Fire
Oct 17, 2008
6,997
Eastern Central PA
I got a few cups of black soot crumbly like substance out of my stovepipe and just out of curiosity decided to see if i could light it up. Well its burns fast and hot. My question is why doesnt this stuff burn up every time i run my stove cuz the flue pipe gets very hot especially right where it comes out of the stove.? Is it because most of the air that would feed the burn is mostly devoid of oxygen?
 

jatoxico

Minister of Fire
Aug 8, 2011
4,218
Long Island NY
Black crunchy crumbly is 2 degree creosote. It doesn't burn off because the temps in the area where it forms are not hot enough for it to burn. Would in the event of a chimney fire though which is why we sweep. It's not the worst since it can be swept but could be better. Hopefully nothing else worse in the system.

I was getting it but insulation/block off plate, better wood and sending more heat up the flue have improved things. Now I get more of a chocolate brown soot.

Friend w/ new stove fouled his cap a little. We took a propane torch to it and the creosote expanded like those magic snakes we used to get as kids then proceeded to burn. Kinda neat kinda scary.
 
Last edited:
  • Like
Reactions: Squisher

Seasoned Oak

Minister of Fire
Oct 17, 2008
6,997
Eastern Central PA
Do those creosote logs help at all with this kind of stuff? I cant brush the chimney now. plus its a brick masonry and may do more harm than good.
 

jatoxico

Minister of Fire
Aug 8, 2011
4,218
Long Island NY
I had decent luck w/ Creo-Soot spray. Some was left at the house when we bought it so I used it. Definitely converted some black to white ash but it only activates when it gets to a certain temp so not sure how high up it worked. Don't know about the logs.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,822
South Puget Sound, WA
Do those creosote logs help at all with this kind of stuff? I cant brush the chimney now.
Sweeping needs to be done regularly. How regularly depends on the wood being burned, the stove and how it's operated, the flue path and how much it cools down the flue gases. If you can't do it, have a pro do it.
plus its a brick masonry and may do more harm than good.
?? not following this concern.
 

Seasoned Oak

Minister of Fire
Oct 17, 2008
6,997
Eastern Central PA
Probably my best bet is a liner .
 
Status
Not open for further replies.