Is it normal to hear some small pieces of creosote dropping in the stovepipe / top of insert?

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Northeaster1

New Member
Oct 10, 2008
119
Nova Scotia
Hi Folks,

We have been using our new PE Pacific (mid sized) insert for about 2 1/2 months now. Heating the area very well. Lots of draft - no trouble starting fires or throwing decent sized spilts on the coals in the morning. Wood may not be bone dry, but reasonably seasoned - starts well - able to get lots of heat, and choke down draft completely 10 -15 minutes or so, after reloading.

We have not cleaned the firebox door yet, in 2 1/2 months of regular, but not always 24/7 burning. Likely have gone through 1 1/2 cord so far. The door has brown, dry looking soot on it, not black and greasy looking.

We have just recently started hearing what sounds like small flakes of cresote falling down a few feet of pipe, and landing in / on insert. I assume it lands above the baffle, so we don't see anything ignite or burn, other than the wood in the firebox.

We have an outside cinder block chimney, with a clean 12x12 clay liner, and then the new solid 6" liner (with a short piece of flex to connect the stove) inside of that.

I have been up on the roof a couple months ago, to see if I could see much creosote. However, with the chimney cap, which is rivetted, you can't look down the liner at all. There was some flakey, dry creosote inside the lip. The liner isn't insulated, other tahn the dead airspace between it and the clay liner. I did install a metal blockoff plate, and the top is sealed.

The top section of pipe, with the cap, rises about 4 ft above the chimney, and is uninsulated as well. There is a clamp which secures the cone shaped rain guard to the top section.

I would like to inspect the inside of the pipe more closely. Should I drill out the rivets, and rmeove the cap to look in, screwing it back together afterwards. Or what about removing the clamp and cone, to see what that gives me access to?

I did not install the liner. Can someone tell me how / where it is suspended? Fior example do they normally use a top bracket, that holds all of the weight of the liner from the top?

Finally, should I worry about the falling creosote sounds, or is that normal?
 
I started hearing creosote fall a couple days ago. Went up on roof and brushed it all out this morning. Also another clue, my draft is poor when flue is creosoted (wood stove).

Yeah, you should at least take the top off and get a look inside, might as well take your brush up with ya too. It needs cleaning no doubt.
 
Thanks for the reply! I will check out the pipe, removing the top cap, and having a look down. If there is a build-up, ca nI just brush taht all down into the insert? Will it just burnup in the top of the baffle / firebox, where it lands. Or should I remove baffle, etc, so it fall right into the box, and then remove it all with shovel, etc?
 
Drop the baffle before cleaning so that the creosote falls into the firebox. You don't want a small mountain of crud in the way of the exhaust. Be sure to have a gasket for the secondary air supply at the back of the baffle on hand. It'll need to be replaced.
 
BeGreen - thanks for the advice!! I hadn't thought about needing gaskets, etc. I will have a look at the stove manual, and call my dealer for gasket availability.

Just wondered how much creosote is OK in the inside of the pipe, and at what point a person says "It needs to be cleaned!" Obviously, if I inspect and see 1-2" of buildup, I would be very alarmed, but what would a normal find be, requiring cleaning?
 
Conventional wisdom is 1/8" to 1/4" of accumulation. If it is dry powder.
 
BB - thanks for the experienced answer!! When I did check the inside rim / few inches of the top pipe, after only a couple weeks of burning, there was no measureable amount. However what little there was was more of a flaky / shiny black susbstance, than dry powder. This may have been only at the top, as it is exposed to much more cold.
 
Update - Took the cap off, and snapped a couple of pics. You can see loose flaky creosote for the top 2-3 ft of colder pipe, but then it really seems to get less, and more powdery. I now have to go to the hardware store and pick up a brush / rods, or some PVC. Will be cleaning from the top.

Nice clear day here, but not warm outside - approx -18C + windchill - nice and sunny though!!

Let me know if anything looks alarming in the photos, please!!!
 

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a couple more pics. You can really see the glossy, flaky stuff at the lip!

Have to wait a couple of hours before cleaning, as I still have a few coals / ashes and the temp is too hot to touch the baffle yet!
 

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Alarming?

I'd have stuck the cap back on and bought a brush and some rods sometime next week and cleaned it in the spring. ;) But, while it's apart, might as well give her a stroke or two.

Not enough creosote in there to hazard stuff too badly if it did light off...


Northeaster1 said:
Update - Took the cap off, and snapped a couple of pics. You can see loose flaky creosote for the top 2-3 ft of colder pipe, but then it really seems to get less, and more powdery. I now have to go to the hardware store and pick up a brush / rods, or some PVC. Will be cleaning from the top.

Nice clear day here, but not warm outside - approx -18C + windchill - nice and sunny though!!

Let me know if anything looks alarming in the photos, please!!!
 
Good to hear that it doesn't look excessive! I am used to working / being out in the cold, so it's still a nice day to do a bit of work outside! Figured if I clean it now, we will defintiely be good till the spring. Like to see how much comes out, as a bit of a benchmark as well.

Thanks for the confirmation! This forum has been a huge help this past few months. Thanks to all who contribute!!
 
FWIW, my PE never has brown on the glass after a good burn. You may be choking down a little too soon.

As for the creosote falling down on the stove, I had that also. I wasn't burning very good wood last year and my PE formed a lot of brown granules right at the base of the flue and in the horizontal flue section. The top of the flue was pretty clean, the creosote didn't make it that far and just fell down to the cleanout or never made it to the collar. I put in an insert and the entire flue has stayed a lot cleaner.
 
Gary - thanks for the advice. I may be choking it down a bit too early on some evenings, but normally I char the new load on high for 5-10 min, then med draft for another 10 or so, and finally air shut down to low.

My chimney was the oppsoite of yours - clean as a whistle near the stove, and dirty in the last few feet. I know I should have it insulated, or cut the top piece shorter, as it goes about 4 ft above the clay chimney. The sweep who installed the liner said we could cut it shorter if we wanted, but to try that and see how it worked.

Anyway, cleaned the chimney. Had a hard time getting the brusk down the top couple feet, due to the buildup. I used the poly brush, and the bristles are quite stiff. Once I got it cleaned out, it was much easier to pull in / out.

Only got about 1/2 gallon of flaky, shiney creosote, so I feel pretty good about the way we have been burning.

here's a couple pic of the bottom section before cleaning!
 

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and the top section after cleaning:
 

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It's time for a good cleaning if we ever get a day 30 degrees or above. I've been burning 24/7 since before Thanksgiving and the log pile is shrinking quickly. My question is the chimney cap is very black. When I take it off to clean the flue what can I use to clean off the black on the cap?
 
I have heard some people talk about soaking it with some flammable liquid and burning it...

I just use a wire brush to get the worst of it off, and stick it back up there. Generally it's nearly back to bare metal when you get done.

Wear a pair of rugged gloves working with the stuff...

searay220 said:
It's time for a good cleaning if we ever get a day 30 degrees or above. I've been burning 24/7 since before Thanksgiving and the log pile is shrinking quickly. My question is the chimney cap is very black. When I take it off to clean the flue what can I use to clean off the black on the cap?
 
I just came across this statement from another site.

"Woodstoves can be burned hot (a full load of wood with air inlets wide open) for a short period (about five minutes to 30 minutes) at least once a day. This procedure is called pyrolizing dries third-degree creosote, shrinks it, and causes it to drop down the flue or be expelled upward with the stronger draft."

I burn hard for 1 hour each day (not with a full load of coarse) so now I know why I am getting black flakes on snow covered roof and walkway.
 
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