Not Happy With New Supaflu Chimney (creosote pics)

[Todd]

Ran a brush down today and got about 1/2 gallon of creosote. Most of it looked like burnt popcorn and there was even some dripping tar in the back of the clean out. Something must be going on here, I ran a brush down back in November and had barely anything. Stove burns clean and wood is 3 years old split. Cap has stayed clean all year and the clean out is also sealed off. Maybe I should have a sweep come out and inspect it with a camera, could be a leak somewhere? Never had it this bad with the old stainless liner.

 

[BrotherBart]

The burnt popcorn look means that stuff lit off. I was very familiar with that with my old stove and chimney.

 

[Todd]

I just don't get why? Maybe there's a crack down below somewhere and it's sucking air? When I brushed I hit something down near the crock. I'll have to take the pipe off and investigate in the morning.

 

[pen]

Do you have a light bright enough to shine clear down it? A cordless spotlight that is 1 million or more candlewatt's works great.

Gotta be something leaking air I'd think

pen

 

[Todd]

Took off the pipe this morning and there is tons of creosote! Never had this much before. The crock had a lot of that popcorn stuff in it and the pipe had a good 1/4" of creosote. Also lowered a drop light down the chimney and it was all clean except the bottom next to the crock. How the heck did this happen? The stove burns clean, wood is bone dry.

My theory is the way I hooked the stove up. I rear vented with a 7" tee to a 6" reducer, then went up with 20" of single wall slip pipe to a 90 elbow that went to the crock. I bet that tee and slip pipe were leaking major air into the pipe causing the creosote and the extra 90 didn't help either. Go figure, I thought my draft was excellent, no smokey reloads and fire always took off great. Back to the top vent.

 

[ScotO]

I'd almost have to say you have a leak of cold air getting in that pipe somewhere. And like BB said, that stuff lit off at some point which backs up the air infiltration theory. Look it over really good and keep us posted....

 

[pen]

My theory is the way I hooked the stove up. I rear vented with a 7" tee to a 6" reducer, then went up with 20" of single wall slip pipe to a 90 elbow that went to the crock. I bet that tee and slip pipe were leaking major air into the pipe causing the creosote and the extra 90 didn't help either.

If that is the only thing that has changed with the system since the last cleaning with good results, then that's where I'd start as well.

Glad you checked it.

pen

 

[Jags]

Todd, considering that you are getting that stuff so close to the stove (as opposed to the top of the stack, where it cools), I would venture to guess an air leak as well. Something is cooling that stuff off real quick as it leaves the stove.

 

[leeave96]

Took off the pipe this morning and there is tons of creosote! Never had this much before. The crock had a lot of that popcorn stuff in it and the pipe had a good 1/4" of creosote. Also lowered a drop light down the chimney and it was all clean except the bottom next to the crock. How the heck did this happen? The stove burns clean, wood is bone dry.

My theory is the way I hooked the stove up. I rear vented with a 7" tee to a 6" reducer, then went up with 20" of single wall slip pipe to a 90 elbow that went to the crock. I bet that tee and slip pipe were leaking major air into the pipe causing the creosote and the extra 90 didn't help either. Go figure, I thought my draft was excellent, no smokey reloads and fire always took off great. Back to the top vent.

When I went from top vent to rear vent after my relining, I had lots of creosote in the pipe (vertical set-up). Once I hooked the stove up to the new liner (horizontal exit from the stove), no more creosote problem - only dust in that pipe out to the liner. The difference was in draft and double vs single wall pipe (my horizontal set-up is double wall). I think in addition to the lack of draft - pre relining, the vertical single wall stove pipe would cool inside much more than the double wall - giving creosote a chance to settle out. BTW, the OD of the double wall matches the OD of the 7 to 6 inch reducer OD, so it looks like the same pipe - easy on the eyes.

On my Keystone, I have the reducer from 7 to 6 inch right on the stove collar. Using that 7 inch tee may be slowing down your exit velocity such that you are getting creosote and build-up instead of going out the chimney. I can also tell you that my Englander set-up had some leaks in the stove pipe that I thought were insignificant. However, when I sealed them (and the pipe seam), the stove performed like a different animal - much better.

So from my reline experience and leaky stove pipe experience with the Englander, I can tell you that it doesn't take much of a leak to lower the draft and allow creosote to form.

Good luck,
Bill

 

[Todd]

Probably was that tee, I didn't gob any furnace cement on the cap and you could see where the air was leaking in. I went to Menards and bought some cheap 24 ga pipe and changed it over to top vent. The pipe temps are almost 100 degrees higher and she seems to be burning much better. I may have to cut down the 3' horizontal or go with double wall if this doesn't work.

Here's a new pic for stump.

 

[leeave96]

Probably was that tee, I didn't gob any furnace cement on the cap and you could see where the air was leaking in. I went to Menards and bought some cheap 24 ga pipe and changed it over to top vent. The pipe temps are almost 100 degrees higher and she seems to be burning much better. I may have to cut down the 3' horizontal or go with double wall if this doesn't work.

Here's a new pic for stump.

Looks great! I think you got it.

Bill

 

[Todd]

Still kind a bummed about all the creosote, could of been a bad deal if I hadn't decided to run a brush down.

 

[Heatsource]

ever notice a chimney fire?
the chunks in your hand look like expanded soot.
a thin glazing expands dramatically when burnt, into something like what you have pictured

 

[Todd]

ever notice a chimney fire?
the chunks in your hand look like expanded soot.
a thin glazing expands dramatically when burnt, into something like what you have pictured

Nope, never heard the roar or saw any other signs.

 

[laynes69]

From what we use to experience on our old furnace, those chunks didn't light off. More than likely the creosote expanded in high heat and continued to collect. Creosote that has burned will be light and ashy. If it looks like glass inside and is dense, I doubt it lit. Must have been a decent air leak.

 

[greythorn3]

From what we use to experience on our old furnace, those chunks didn't light off. More than likely the creosote expanded in high heat and continued to collect. Creosote that has burned will be light and ashy. If it looks like glass inside and is dense, I doubt it lit. Must have been a decent air leak.

heck them chunks might make some good firestarters.

 

[Woody Stover]

Probably was that tee, I didn't gob any furnace cement on the cap and you could see where the air was leaking in. I went to Menards and bought some cheap 24 ga pipe and changed it over to top vent. The pipe temps are almost 100 degrees higher and she seems to be burning much better.

Good deal...and it'll be easy to take "Not" out of your thread title. :smirk:

Like Bill's, my Keystone setup was rear-vent, 7"-6" reducer at the flue collar, 6" tee, 6" insulated flex liner, FWIW. 17' stack. I didn't seal anything and didn't see much 'sote.

 

[Stump_Branch]

Probably was that tee, I didn't gob any furnace cement on the cap and you could see where the air was leaking in. I went to Menards and bought some cheap 24 ga pipe and changed it over to top vent. The pipe temps are almost 100 degrees higher and she seems to be burning much better. I may have to cut down the 3' horizontal or go with double wall if this doesn't work.

Here's a new pic for stump.

Im not sure if its the overall size of the hearth, the raised portion, or just brick color, but i do love the looks of it. Haha i can tell you that the built in tool holders are my favorite. Much better than the chincy stand you typically get.

I still contend that it really shouldnt matter rear or top vent with a reverseable flue collar, but your probably right that this is the better setup. I think when i do the jotul downstairs ill be going double wall.
My fireview hits a T in the back right to a liner. I do wonder if that 7in to 6 doesnt play a part in all this. No idea why the keystone needs a 7in anyways.

 

[Todd]

I did a little more experimenting by switching out the cats in both stoves. I've been running the new steel cat in this stove for a year and the other stove upstairs has a 2 year old ceramic cat that doesn't see as much use . I switched them back and forth after cleaning the chimneys and now I think the steel cat may be degrading or not running up to par. The ceramic cat burns hotter for a longer time and I also seem to get a longer more complete burn. The steel cat seems to take a little longer to get up to the 500 mark and lately it doesn't go much above that. At the beginning of the burning season I really didn't see much of a difference between the two. Maybe the steel cat had a little more to do with this creosote problem than the chimney or pipes?

Contacted Woodstock and they are forwarding this info to Sud Chemie who is the manufacture of the steel cats. I tried emailing and calling them last week about this but never received a response.

Also talked to a guy at Applied Ceramics and he said they don't make the steel cats, didn't think they lasted more than 3 years and they seem to come out about every 10 years or so then go away because they don't last and the ceramics burn hotter.

 

[Todd]

After a month of burning with a ceramic cat and switching out the rear vent to top vent I took apart the pipe and checked the chimney, there was barely a lick of creosote anywhere, just a bit of dusty soot. I feel much better now.

 

[begreen]

Ahhhh. Nice to hear this one is solved.

 

[corey21]

Glad to hear that it is working out better.

 

[rideau]

Missed this thread in January, Todd. I'm really glad you cleaned that pipe when you did. Would have scared the dayligts out of me. I'd have been checking that pipe daily for a while. That's just plain frightening. Think I'll check my pipe next time the stove is cold...Really glad you caught that and are OK. REALLY, REALLY glad.