Stage 3 creosote after less than 1 week - pics included - new Jotul f400 Castine

[Propane_Poor]

Hi all,

I'm back for more help, if you please. =)

We started burning our new Jotul f400 Castine stove about a week ago. Week 1 of heating with wood. 2 days into it I realized our wood wasn't up to snuff, probably in the 20s % moisture content. I got a moisture meter and that's what some of it was measuring.

So we swapped a load of 2/3 year seasoned ash and etc which is reading about 12 to 15% moisture and have been burning that the past 4 or 5 days. This is on the inside face of a fresh split at room temperature.

I went up on the roof today to check the chimney and see the following: yellow discoloration on the outside of the pipe, brown glue-like substance around the rain cap fitting, and a shiny black coating inside the rain cap and flue.

Evidently something is extremely wrong but I don't know what. We have 14' of flue from top of the stove and have been hitting 400+ degrees on every burn, up to 500 and 600 fairly often. The glass is keeping itself clean. The stove pipe is Selkirk double wall going into Selkirk Supervent double wall stainless, all straight vertical.

I turn the air to 75, 50, then 25 in increments. Ive done it too fast a few times and smoldered a few, but just right some other times and gotten a nice extended burn with secondaries.

Apart from a few rookie mistakes since we are learning, I'm not sure how we could have caused this so quickly.

A couple of thoughts, with cons:

1) Maybe I should add another 3' of chimney? It will look ridiculous and I already have 1 support bracket on the 7' above the house (small single story ranch)

2) maybe I shouldn't run a fan across the top of the stove? If it's cooling the stove pipe could that cause buildup?

3) Maybe burn a creosote removal log every couple of days? That may hurt the wallet though.

4) No idea about the stainless discoloration yet..


I'm currently burning it with 2 large splits sitting E/W on top of 2 smaller splits sitting n/s. 500* on top, secondaries glowing, and air at 25%. Outside temp is 45*.

I tried to cover as much as possible in this post to hopefully narrow it down to the right solution quickly. Otherwise not sure if I should be concerned to continue burning.

Thanks so much,

 

[Propane_Poor]

Just had another thought... I wonder if my stainless chimney is itself too tall... Could it be cooling down too much and forming creosote by the time the exhaust exits the flue since there's 7 feet out of the house?

If that's the case then I can't extend it further and this stove probably won't work. Hmm.

Sent from my SM-N960U using Tapatalk

 

[jatoxico]

If the stove is drafting ok then I don't see where adding more pipe will be needed. And it may not be as bad as you think, The cap is always the weak link in the chain and the creosote could be from your first few burns esp if it was raining or something. More air and sending some heat up the flue is the best. Chasing burn times is attractive but can cause you issues until you figure out what you're doing. Where are you taking the temperatures you cited?

 

[Propane_Poor]

Thanks jatoxico, its in my top 3 foot section as well, unfortunately not just the rain cap.

Currently sitting watching the fire and I've got 2 thermometers on it, one on each side or the stove top as per the manual. I also have an IR thermometer and am reading now between 550 and 650 across the whole top.
The thermometers I have must read high as one says 700. And it said almost 600 in my 460 degree oven.

Sent from my SM-N960U using Tapatalk

 

[kennyp2339]

looks like the pipe is being broken in, keep you stove top north of 500deg f and youll be fine,

 

[Propane_Poor]

Also not one hundred percent sure it's drafting okay. I do get some smoke spillage sometimes but that seems to be a common issue with this model.

Sent from my SM-N960U using Tapatalk

 

[MAD MARK]

"2) maybe I shouldn't run a fan across the top of the stove? If it's cooling the stove pipe could that cause buildup?"


That might be a good conclusion. Of course if its double walled shouldnt matter much. Maybe purchase a probe temp and get a better reading at the flue.

And those are the wrong type of shoes to be climbing a roof on. Just an observation of safety.

 

[kennyp2339]

Nice stove btw, for the smoke spillage issue try bumping open the air all the way a full 2-3 min before opening the door, this might alleviate some.
14ft stack straight up from the stove collar? That's almost the minimum threshold for chimney height (I can remember if it was 12ft or 15ft for this stove) you may want to try adding a 3ft section especially since your burning while the temps are in the 40's, the draft will increase when the temps get into the lower 30's, but give it a shot.
As you are aware the wood supply needs to be 20% or lower.

 

[Propane_Poor]

Thank you, can a probe thermometer be used on double wall?

Understood with the boots. Went straight from splitting firewood to checking the chimney and didn't think to change. Our roof is very shallow and easy to walk on thankfully.



Sent from my SM-N960U using Tapatalk

 

[Propane_Poor]

Nice stove btw, for the smoke spillage issue try bumping open the air all the way a full 2-3 min before opening the door, this might alleviate some.
14ft stack straight up from the stove collar? That's almost the minimum threshold for chimney height (I can remember if it was 12ft or 15ft for this stove) you may want to try adding a 3ft section especially since your burning while the temps are in the 40's, the draft will increase when the temps get into the lower 30's, but give it a shot.
As you are aware the wood supply needs to be 20% or lower.

I think it calls for 14 or 15. I have 14 and was hoping it would be enough. Any more will look silly on our short ranch. It's not bad when the fire is roaring but I'm wondering if it's causing inadequate combustion during the secondaries.

Sent from my SM-N960U using Tapatalk

 

[MAD MARK]

I think it calls for 14 or 15. I have 14 and was hoping it would be enough. Any more will look silly on our short ranch. It's not bad when the fire is roaring but I'm wondering if it's causing inadequate combustion during the secondaries.

Sent from my SM-N960U using Tapatalk

If the fire is roaring, that causes flue temps to rise which would help in aiding no creosote forming in chimney pipe.
If good secondaries usually means wood is off gassing.
I am guessing the buildup in the chimney is from wet wood/burning too low.
What are you using to measure the wood?

http://www.condar.com/Probe_Thermometers.html <--Double wall temp probes.

 

[begreen]

Also not one hundred percent sure it's drafting okay. I do get some smoke spillage sometimes but that seems to be a common issue with this model.

If the stove is top vented with 16'+ flue it shouldn't spill smoke with temps under about 45. Is there single or double-wall connecting stove pipe on the F400?

The initial gunk on the top part of the chimney may have been from the damp wood burning. There isn't much there so you could try running a 700º fire with a bit more wood and air in the stove to try and burn the film out.

 

[Propane_Poor]

If the stove is top vented with 16'+ flue it shouldn't spill smoke with temps under about 45. Is there single or double-wall connecting stove pipe on the F400?

The initial gunk on the top part of the chimney may have been from the damp wood burning. There isn't much there so you could try running a 700º fire with a bit more wood and air in the stove to try and burn the film out.

Currently it's 14'. Inside is the double wall stove pipe. Above the house I have 7 feet, in the form of 2x 2' and 1x 3' sections.

We went out this evening and I picked up some Rutland granular creosote remover to start using, as well as a small pack of Kwik Shot capsules. I also am considering replacing the aforementioned 2' chimney sections with 3'. That will give me 2 more feet without additional points or needing to move my chimney support bracket.

Sent from my SM-N960U using Tapatalk

 

[jrems]

I don’t see much to worry about. The top 2-3 feet of pipe and the cap will be much cooler than the rest of the chimney. You will get much more deposits on it than the rest of the pipe.

 

[Ctwoodtick]

If the stove is top vented with 16'+ flue it shouldn't spill smoke with temps under about 45. Is there single or double-wall connecting stove pipe on the F400?

The initial gunk on the top part of the chimney may have been from the damp wood burning. There isn't much there so you could try running a 700º fire with a bit more wood and air in the stove to try and burn the film out.

I agree. After one week, you can only have so much buildup. Although it’s scary seeing stage 3 creosote at all, I agree that you can burn a little hotter and the buildup should convert to a sweepable less volatile type of buildup. I had the same situation last year early on in the season and the glaze essentially went away after burning a bit hotter more regularly.

 

[Ludlow]

What wood species are you burning?

 

[firefighterjake]

I wouldn't worry too much . . . like others I suspect the ooey-gooey creosote you saw was from burning the sub-optimal wood you were using before. At this point I would just keep burning . . . if your wood is now good and you are running at the right temps you should not have as much cresote build up.

That said, if it concerns you, tossing a creosote converting clean up log or powder most likely will not hurt things and could give you a bit of peace of mind.

 

[xman23]

The first year mine was exactly as yours is. Plugged the screen in a month. The cap was a wet gooey mess. The chimney had glazey hard chip build up. As my oak became seasoned, each year it got better. Now years later nothing has changed, except seasoned wood. The cap gets a bit black, but dry.

So this year watch and clean the cap, screen a lot. And for piece of mind do a mid year cleaning.

 

[Kevin Weis]

Sounds like nothing abnormal here. No matter what and how you burn your going to get some creosote formation at the top albeit should be minimal typically. To have nothing there after a few months of burning I think would be impossible. But just saying as I'm not an a expert by any means. Kevin

 

[Allagash350]

I have the same stove and would not worry. When I cleaned my chimney this fall the top cap looked terrible. However the rest of the liner only produced 2 cups worth of creosote.
In my opinion with the temps you are reporting your chimney is most likely spotless.
Great stove by the way !

 

[Propane_Poor]

What wood species are you burning?

I believe it's a mix of maple, Ash and elm.

Sent from my SM-N960U using Tapatalk

 

[Propane_Poor]

Thank you all for the input. I'll get up there in a week or so and check things out.

I added 2 more feet of chimney this morning (and adjusted the brace accordingly) so I now have 10' out the roof and 16 feet total stack. It's still in the 40s outside here and I think the draft seemed noticeably improved on starting this morning too.

It's now too tall that I won't be able to clean or inspect without disassembly. Ah well. Maybe I'll figure out how to use one of those Soot Eater tools from the bottom up.

Sent from my SM-N960U using Tapatalk

 

[jatoxico]

It's now too tall that I won't be able to clean or inspect without disassembly. Ah well. Maybe I'll figure out how to use one of those Soot Eater tools from the bottom up.

I can recommend the Sooteater. Works great without having to get up on the roof.

 

[BlazeKingSaddles]

Was hoping someone from this thread could offer some advice. This morning I reloaded the stove (Blaze King Ashford 30) on top of a bed of hot coals and got the fire going. Just before the cat went into active, smoke started pouring out of an upper joint of the chimney (6” double wall pipe). I closed the bypass and switched the stat to all-the-way low. That stopped the smoke, but I noticed the smell of curing, e.g. the smell a new stove and chimney make on the first fire. I’m assuming I had a small chimney fire, which might explain the smell (pipe became hotter than it had ever before) but I can’t understand why I would have any major creosote build-up, as I had my chimney professionally swept a month ago, I burn very hot EVERY reload (500-550 degrees F) for about 45 mins before touching the stat, I have great draft (30 foot straight pipe with no bends) I typically keep one continuous fire going and (finally) The entire set up is less than a year old.

Not sure what to make of this problem and any advice would be very much appreciated!

 

[Highbeam]

Was hoping someone from this thread could offer some advice. This morning I reloaded the stove (Blaze King Ashford 30) on top of a bed of hot coals and got the fire going. Just before the cat went into active, smoke started pouring out of an upper joint of the chimney (6” double wall pipe). I closed the bypass and switched the stat to all-the-way low. That stopped the smoke, but I noticed the smell of curing, e.g. the smell a new stove and chimney make on the first fire. I’m assuming I had a small chimney fire, which might explain the smell (pipe became hotter than it had ever before) but I can’t understand why I would have any major creosote build-up, as I had my chimney professionally swept a month ago, I burn very hot EVERY reload (500-550 degrees F) for about 45 mins before touching the stat, I have great draft (30 foot straight pipe with no bends) I typically keep one continuous fire going and (finally) The entire set up is less than a year old.

Not sure what to make of this problem and any advice would be very much appreciated!

Was your door cracked open while the fresh load got going?

30’ stack, reload on hot coals, full throttle, bypass open. You could easily have sucked flames up the flue far enough to burn off the debris.

No flue damper for your stack? You are most likely two or three times over the maximum limit for draft. Have you ever tested your draft strength?

I had a similar flue combustion event a few weeks ago. Chimney had been swept which is why it was not a huge event.