Sorry I thought you had said you saw sparks but I went back and read it I was wrong. But still there is enough in that pipe to burn. And if you saw a glow I don't see any way it could be anything but a small fire. Again I doubt it was enough to damage anything just because there was so little fuel. But pretty sure it was a fire
Chimney fire after two weeks???
- Thread starter Woodsman on the Plains
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Hmm, I guess I need to figure out what is going on then. I did notice that the installer didn't have the pipe pushed down fully on the top of the stove. Could that maybe (possibly) allow enough air to come into the double wall part enough for it to condense and then it warms up enough once it hits that class A and leaves less accumulation on the class A than the double wall?
An air leak could definitely be the problem. It's also possible the whole chimney looked like that before the fire as well. There really is no way to tell at this point. Just make sure everything is installed correctly and you run properly.
kennyp2339
Minister of Fire
Round class a all the way up... outside skin would be discolored in the section that had the fire, also check your cap for expanded creosote if there was a fire.
Alright folks, did a sweep today. Definitely have some shiney starting to form towards the top. Got quite a bit of sweepings. More than expected with a cat stove (supposed to run clean I thought). Installed a condar probe today as well. When I put it back together I shoved it down as far as I could on top of the stove and gained almost 3/4 of an inch. Now I have exposed screw holes because the installers didn't make sure it was down all the way on top of the stove. Then the craziest thing happened. I have never had an issue with draft until today. I went to fire it up and smoke just started rolling out the front. So I shut the door and it started rolling out of the air intake...😳... I shut the air down and opened up the windows and it started to draft again. Is it possible that since it wasn't seated fully on the stove top that it was creating more draft and cooling things down to much? I have no idea. It was really bizarre. Anyway after I got it cruising the probe hit 900 f so I turned it down where I usually keep it at 90°. Went back down about 30 minutes later and probe was about to hit 300°. So I turned it back up and now I'm cruising at 500° flue temp. My thought is I would like to turn it down more to get 12 hours out of it but with only be able to turn it down a 1/4 to keep it at 500° I will be going through way more wood than I was expecting. At this point I should have just got a tube stove. Is my cat not working properly? Is that why I had so much built up already? Mind you my flue is 28' so pretty long run. Insulated class A all the way except the double wall bottom 4'. Just wondering what I can do to keep the build-up down.
One thing I can confirm, my chimney is much dirtier when using a cat stove than a modern noncat. More smoke emissions too. Totally worth it.
kennyp2339
Minister of Fire
Make sure the smoke pipe isnt below the flue collar into the fire box, the smoke pipe should be flush with the bottom of the stoves flue collar.
Ya I'm noticing that. My tube stove upstairs just gets some dusty accumulation that wipes off with my fingers. I'm just going to have to figure out a totally different routine for the BK, but that's OK. I'm sure it's worth it as everyone seems to love them! I really do like it, it's just not what I'm used to.
He means on the inside. The part you stuff into the stove collar can't go in so far that it hangs down below the top plate of the stove when looking or feeling from the inside. I'm not so sure that it's a deal breaker but certainly undesirable.
This stove is awesome! Now that I put a flue probe in and can monitor my flue gas temps I am finding this thing much more reliable and easy to use! I suppose I won't really be able to tell what the build up will be but I suspect it will be minimal now that I am able to keep flue temps around 3-400 consistently. What I have found is I think I was turning it down too far. If I turn it below 55% the temps go down to 200-250° and I can get super long burns (14-16 hrs) that way but I can still get 10-12 hours on 55% and keep flue temps above 300°. I wish it was standard practice for these installers out here to put a probe in right away so a homeowner can adjust the burn according to the unique installation of their home. With my extra long flue I feel it pertinent to keep my temps up to the 300 or more range to keep build up to a minimum.
Thank you everyone for your help and advice with this matter. We'll see what it looks like when I sweep it in a few months!
Thank you everyone for your help and advice with this matter. We'll see what it looks like when I sweep it in a few months!
how big of an area are you heating? i would find it hard for any stove to throw out enough heat over a 14-16hr period to heat anything beside a small area.
I heat 4,600 square feet with wood. I do have a propane furnace that is set for 65 but it never kicks on unless I get lazy and don't feel like loading the stoves and turn it up to 70. I heat the 2,300 sq ft basement with the Sirocco 30.2 and the 2,300 sq ft main floor with my Valcourt Lafayette 2. This is the first year with the Sirocco and burning wood in the basement and honestly I only need to have a fire upstairs once a day now and the house rarely dips below 70. Unless it's really cold...like a few weeks ago it was -26 f and I had both stoves going on medium-high all day. Granted it's a newer house so the insulation probably helps out a lot. And as for the burn time I'm at 10-12 hour cycles with the Sirocco.
wow, that's pretty incredible. I would be so happy with a 10-hour burn being able to keep my 2000 sqft warm. I'm pretty sold on the Ashford being my stove for next season.
Did you do spray foam insulation or batt? My Maine camp is 2000sqft new construction with batt, and the Encore cannot keep it warm overnight, and max burn on absolute low is 7-hours or else i have to relight it. So far ive been running it overnight mid throttle to keep the house warm and waking up halfway through the night to restock it but I am about done with that.
I have 2x6 walls and did the BIBS system (blow in blanket). Basically they put fabric on the interior wall and blow the cavity with a blow-in material. It makes it R-21 instead of the R-19 batt. If I could do it again I would do a dense pack which would bring it up to a R-23. The kicker is my attic is blow-in R-50. I actually think I might add 6" to bring it up to R-65 but I haven't decided yet. The house is a fairly open floor plan except for the bedrooms which I'm sure helps as well. I'm sure if I lived somewhere where it's like 10° all the time it would be a different story. It's usually like 30-40° during the day around here except for the occasional 4 day cold snap.
Can someone please tell me what my flue temps should be at during startup after running the stove on high for the 30 minute recommended time frame? Maybe @bholler or @Highbeam or @BKVP? Or anyone really for that matter. I put that probe in and now it's freaking me out. My flue temps regularly hit 950-1000 after 30 minutes on high. My pipe should be able to handle it as it's class a rated for 650 C, but it's just freaking me out. When I turn it down slightly it goes back down to 850ish then 5/8 down is 350-400. Thoughts?
Don’t run it for 30 minutes on high if your flue temps exceed the safe zone. Class a is only rated for 1000 degrees F continuous. Anything above 800 or so is purely waste.
That 30 minute recommendation has been downright dangerous for me with softwoods. You’d think that since BKs are designed in softwood country that this would have been noticed.
hey I just wanted to chime in on what your sweep said.
Maybe it's just my VC stove, but I disagree with him.
I used very well tested dry wood (<19%MC), and if I dont run my stove fairly hot, I can get my flue very dirty.
I had a 'creosote burn off' aka chimney fire about 3 weeks into burning only maybe 10 fires? I was trying to run the stove as cool / long as I could to produce a long even amount of heat, and running it without a cat which helps burn up some of that smoke before it hits the flue.
So I set out to determine what my flue would look like after just a couple of burns running like this. I should clarify, a burn to me is a day and night of burning. Daytime usually run a bit hotter/quicker and night being at 400 or sub 400 STT. At the time I didnt have a probe to check the cat area temps. I was aiming for what a stove is supposed to be for, putting out heat - but trying to avoid too much heat too quickly resulting in a morning time chill. ON both days I turned the air down too far, and still had 1/3to1/2 wood left in my stove in the morning, albeit it very blackened wood with black glass.
Pictured, are the results. From the flue collar up.
![[Hearth.com] Chimney fire after two weeks???](https://www.hearth.com/talk/data/attachments/308/308960-c991df7570910adebc638ec19173b231.jpg?hash=LVHBV9SoNT "[Hearth.com] Chimney fire after two weeks???")
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Honestly I think I'm having the same thing happen. That's why I've been burning HOT. To keep build up down. What is your stove? And what was your solution? Burning hotter like me or did you try something else?
Edit: I need to fully read twice before I respond as you stated in your post that it's a VC stove...🤦♂️ my bad
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Honestly I'm starting to wonder if I need a key damper. Wondering about drafting issues (especially with reaching high flue temps at startup). 27.5 feet of chimney pipe coming straight up out of the basement. From my understanding basements have a negative pressure issue so that combined with 10 ft of extra pipe shouldn't cause overdraft. (At my altitude BK recommended minimum flue height is 17.5 feet). However, it may be possible as I really don't seem to have issues getting a draft started. And I'm not really thinking I have air leaks as the fire is easy to control. Also in regards to pipe temperatures the tag on the back of the pipe says regularly producing 650° C flue gas temps, I'll attach a picture.
![[Hearth.com] Chimney fire after two weeks???](https://www.hearth.com/talk/data/attachments/308/308961-352c2d0104bceec85c44a8b3f708c180.jpg?hash=JoXXieEOGY "[Hearth.com] Chimney fire after two weeks???")
See that's why I'm on here! As someone just starting to get into this it is great to learn stuff like that! Thank you for clarifying that. I appreciate it. See no one tells you these things when they install so I gotta learn it all.
Well, Im not entirely sure I solved my problem. The other day I looked up in there and while the sides most of the way up were just that dull gray and roughish feeling with no ability to remove anything with a fingernail, I could still see shiny flakes right around the elbow area, which makes sense.
What I've been doing is making sure Im not smoking the wood. I make sure I see a flame in there at all times or a nice glow of wood that has turned to coals taking up 1/4 of the box on the bottom (usually that only happens about 1/2 - 3/4 the way through burning a load of wood). This equates to higher STT temps than I would like if it were cooler outside and I was using the stove to heat the place during the warmer spring/fall days.
It's really odd to me. I put wet/sappy wood into my fireplace, it burns and in 8 years Ive cleaned this chimney twice and have probably gone through 20 cords in that fireplace. At best I might end up with a cup of black dust...MAYBE. It's almost like my flue pipe should be bigger. My flue pipe is INSIDE for this very reason, to avoid the cooling gases and creosote build up. SO that's why I have been burning hotter.
Startup, I have to avoid using too dry of kindling and too small, otherwise the flames / heat build up my flue temps too much. It also doesnt generate a nice bed of coals to put 1/2 the box full of small/smaller medium splits for my next coal build up fire, which is what I must have in order to full load the stove else it will be too hard to keep flaming and may either overheat or just go out making tons of creosote.
For me the build of up a nice coal bed is paramount to success.
