Creosote buildup on rain cap

[Sean Truesdell]

Hey everybody,

So I was up on the roof today blowing leaves out of the gutters and figured I would take a look at the top of the chimney and see how things looked after my first month of burning wood in the new PE summit insert. I had (what I consider) a substantial amount of creosote buildup on the bottom of the rain cap. The creosote also appears to be dripping down on to the top of the chimney crown and staining it brown. Are these results typical after only a month of burning during the shoulder season? Thanks in advance for the input!

 

[Jags]

I have seen worse. Its not "bad" but I wouldn't consider it "great" either (for one month of burning).

What kind of temps is your stack temp running?

 

[Sean Truesdell]

I have seen worse. Its not "bad" but I wouldn't consider it "great" either (for one month of burning).

What kind of temps is your stack temp running?

Not sure about the stack temps, it's an insert and I have no way to measure that. I know that some of my wood supply is reading a bit over 20% on the MM but only around 22-24%. It burns well and always get the secondaries going before cutting the air down. I don't have any of the other common complaints about wood not burning or the glass turning black with my fuel but still feel like the increased moisture may be a factor here.

 

[Jags]

Your wood doesn't sound too bad. If it starts and burns fine under normal operating conditions then you should be good to go. I wouldn't be too concerned at this point, but I would just keep an eye on things. I always recommend that a new person takes a mid season inspection of the whole system (stove, pipe, cap, etc.). It will give you a good feel for how things are progressing.

 

[Sean Truesdell]

Thanks for the advice Jags. I'll keep my eye on things and will plan for a good mid-season inspection and possible cleaning.

 

[jeffesonm]

At the end of last season my rain cap was covered in creosote but the liner itself looked great... only got a few cups of anything when I swept it. Do keep an eye on that expanded steel bird screen though... mine clogged up so I just took it off.

 

[BrotherBart]

At the end of last season my rain cap was covered in creosote...

Like this?

 

[jeffesonm]

Yup, a lot like that. Right around the end of the season, the stove started drafting poorly and I couldn't figure out why. Climbed up on the roof and the cap looked a lot like that. I've got 15' of rigid DuraLiner, burn pretty dry wood and the inside of the pipe had just a fine dusting of gray/white ash, so I just removed the screen.

 

[richmhv]

I had a cap like that with my old Better N Bens 901 insert. I used to have to get on the roof sometime in December before the snowing started and clean the screening or I would have a near blockage by February. It would look like Brother Bart's picture. Now I have a round rain cap,no screen, and a cleaner burning stove. The deposition was worst on the screen , not much on the underside of the cap. The chimney itself stayed clean. Caps are cold relative to everything else in the chimney and condense a lot of creosote if you do slow burns especially with the older stoves. Lots of overnight fires on 10 degree nights.

 

[BrotherBart]

We had one member that used to shoot the cap with a pellet gun.

 

[richmhv]

I actually tried to whack it with my fiberglass chimney poles. There was just no substitute for going up there with a screwdriver and chiseling all the black stuff off the screen. It was always the solid crunchy kind, not the liquid creosote that's supposed to be more dangerous.

 

[JayD]

Years ago My dad had one of those bird screens that would do that, Pain in the Arse. I bought him a new cap without the screen. No problems no birds all is well

 

[Excavator]

My cap is same way but I remove twice a year when I brush the liner. I just use flat screw driver and it cleans up good.

 

[Charles1981]

Is that buildup just from the past month or two? It will continue to accumulate. But again if there is a spot to collect creosote that is it. I clean my chimney out mid Jan/Feb and brush the cap off. The first year it was real bad but i was burning some wet wood. The past year it was not as bad with more seasoned wood. Maybe hopefully this year it wont be noticeable now that I am all caught up for the next 2 years.

 

[bholler]

It was always the solid crunchy kind, not the liquid creosote that's supposed to be more dangerous.

That solid stuff can catch as easily as the liquid stuff the only benifit is that it wont run down the chimney to where it is more likely to get ignited. It is not uncommon to have this happen though everything it nice and hot till you hit that cap that is bare metal out in the cold and things condense.

 

[BobUrban]

Cap gets cold up there in the elements as mentioned - this is not uncommon even for those burning >20% wood. The smaller the screen the more likely it is to clog up. Many forgo the bird proofing to avoid this. One member talked about just removing the cap altogether for the winter - which is not a bad idea if this is an issue and you are burning 24/7