"Dirty" Blaze King windows

OhioBurner©

Minister of Fire
Aug 20, 2010
1,535
Center of Ohio
Oh and @St. Coemgen didn't mean to come down on you hard before, but seems you are not familiar with how a stove operates that is equipped with a catalytic combustor, which burns the exhaust gasses much like in an automobile. The advantage of the catalytic stove is that you don't need to have active flames and high burn rate for the combustor to operate and properly burn the volatile gasses. An EPA stove with secondary burn tubes need to maintain a much higher temperature (and active flames) to burn clean, like you said. With a cat stove, even with a very low smoldering fire, there is enough heat to function the combustor, and all those gases get burned even though the firebox is dark, and perhaps coated with soot from the smoldering firewood.

For example I took a couple pics last night after I got my stove up to temperature:

IMG_1678-1080.JPG

As you can see the door is heavily sooted, and no flames in the firebox. If you look very closely though, above the door you'll see the catalyst probe (might have to zoom in) its upside down but reads ~1200F. That is right above the combustor, so you can see there is definitely something going on in this stove despite the lack of fire and relatively cool firebox! The stove is full of 2-3yr css ash firewood.

And here it is:
IMG_1677e1024.JPG

I popped the lid up just for a couple seconds so you can see the combustor working, all that smoke from the firebox has to pass through this. It is very effective at combusting all the smoke.

The glass cleans itself fairly well with the next fire, usually just an inch or so of sooting remains in the bottom corners. I always wondered if the BKs could be run so the glass stays clean since I do often hear about the dirty glass, good to know they can be run fairly clean too if wanted. And nice looking stovese there @Ashful
 
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jetsam

Minister of Fire
Dec 12, 2015
4,962
Long Island, NY
youtu.be
As OhioBurner just said- Running that low, there is not much to see even if you were to clean the glass daily. (I never clean my glass; when it gets cold enough, the glass cleans itself, otherwise it dirties itself faster than I can keep up.)

I do enjoy it when it gets so cold that the stove looks like a fireplace. On the other hand, I am not going to sacrifice my ability to keep the room temperature right where I want it just for a light show. (Not on a regular basis, anyway- exceptions have been made. :) )

I just topped off my Princess after about a 10 hour lowish burn, on my way into work. It was 40 outside and 75 inside tonight. Stove had started with a minimal bed of coals (I just shoveled out the ash this load). Put about 3/4 of a full load in there, 1 year css maple and oak (no, the oak's not dry yet, but I have lots of it).

Here's what was left after 10-11 hours when I topped it off before work:

Image-265736586.jpg

(Yeah, that could have gone another 8 or 12 hours.)

Here's what the stove looked like 1 minute after closing the door and cranking it down again:

Image-1145137028.jpg

So whether the glass is dirty or not is almost a moot point- there's not much to see in there anyway, because it's too warm outside! (High of 43 today. I run the stove at about 20% on the thermostat for 50 degree days, maybe 25% for 40 degree days. That keeps the ground floor at 75ish.)
 

greg66

New Member
Oct 21, 2017
13
g
The level of glass deposits increase by model, based upon depth of firebox. Sirocco 25, all 30.1 and 20.1 models have much cleaner glass than King or Princess models.

Variables such as fuel length, MC, orientation of wood in loading, draft etc. can also have an effect.
@BKVP
just bought a new bk stove, a sirocco 20, i would greatly apreciate if you could elaborate on those variables, and their effects on glass cleaness.
thanks
 

jetsam

Minister of Fire
Dec 12, 2015
4,962
Long Island, NY
youtu.be
I have a Princess. Glass is black for shoulder season (which is fine as there's nothing to see in the firebox anyway). Glass cleans itself in the winter when there's flame to see- convenient!

Firebox temperature is such a big part of the equation that it dwarfs all that other stuff. Since you set firebox temp on the thermostat, things that you'd ordinarily expect to influence the firebox's heat (like MC and draft) don't effect it so much. For example, burn two loads, one dryer and one wetter, on the same thermostat setting. The wetter load will naturally burn cooler.... but then the thermostat opens the intake air to warm it up to the desired temperature (within limits). Of course, if the wetter load is so much wetter that it exceeds the thermostat's air opening range, all bets are off.

Even with the dirty old Princess, the glass is clean when there's fire to see- and this is from a guy that was bringing in soggy deadwood and burning it the same day the first winter. Don't sweat it! :)
 
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BKVP

Minister of Fire
@BKVP
just bought a new bk stove, a sirocco 20, i would greatly apreciate if you could elaborate on those variables, and their effects on glass cleaness.
thanks
Give me a call before 9:00 a.m. tomorrow PAT. I'm not near computer now. Just cell phone. 509-522-2730. Thank you.
 

BKVP

Minister of Fire
Pacific Standard Time...hate auto correct.
 

tarzan

Minister of Fire
Jan 16, 2014
1,552
wv
As OhioBurner just said- Running that low, there is not much to see even if you were to clean the glass daily. (I never clean my glass; when it gets cold enough, the glass cleans itself, otherwise it dirties itself faster than I can keep up.)

I do enjoy it when it gets so cold that the stove looks like a fireplace. On the other hand, I am not going to sacrifice my ability to keep the room temperature right where I want it just for a light show. (Not on a regular basis, anyway- exceptions have been made. :) )

I just topped off my Princess after about a 10 hour lowish burn, on my way into work. It was 40 outside and 75 inside tonight. Stove had started with a minimal bed of coals (I just shoveled out the ash this load). Put about 3/4 of a full load in there, 1 year css maple and oak (no, the oak's not dry yet, but I have lots of it).

Here's what was left after 10-11 hours when I topped it off before work:

View attachment 188439

(Yeah, that could have gone another 8 or 12 hours.)

Here's what the stove looked like 1 minute after closing the door and cranking it down again:

View attachment 188440

So whether the glass is dirty or not is almost a moot point- there's not much to see in there anyway, because it's too warm outside! (High of 43 today. I run the stove at about 20% on the thermostat for 50 degree days, maybe 25% for 40 degree days. That keeps the ground floor at 75ish.)
Your reply this season is eerily similar to your two replies on this thread last season;lol
 

jetsam

Minister of Fire
Dec 12, 2015
4,962
Long Island, NY
youtu.be
Your reply this season is eerily similar to your two replies on this thread last season;lol
I'm glad you remember what I said last year, because I don't! :)

Maybe next time I want to respond to something, I can just drop you a line and you can link one of my old posts...


Edit: LOL, I just looked at this thread on my computer, and saw that my previous post was just one post up from the necro post. That's not immediately obvious when I'm reading hearth on my phone, like usual. Still using tarzan as my previous-post index, tho.
 
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jetsam

Minister of Fire
Dec 12, 2015
4,962
Long Island, NY
youtu.be
Meh, I don't think forums should lock any thread unless it is really having a hard time staying civil.

Something that was interesting in 2007 can still be interesting in 2017, and it brings all that old discussion to the attention of new members.

Off-topic locks are antiquated, too. It used to be required to maintain any type of forum searchability (if the discussion doesn't match the topic, how will you ever find the thread you're after?). Modern search engines, internal and especially external to the forum software, have rendered that a bit of a moot point.

I think it's the librarian in me that is offended by suboptimal use of information there. :)
 

begreen

Mooderator
Staff member
Nov 18, 2005
85,972
South Puget Sound, WA
These old threads are funny. It's too bad they don't autolock after a certain timeframe.
I'd like that too. Too often folks start up a dialog with someone long gone. Or the stove model has been updated or discontinued. If you want to resurrect an old thread and you are the author, ask a mod to open it. Otherwise, if the thread is locked, put a link to the old thread/topic in a new thread.
 

begreen

Mooderator
Staff member
Nov 18, 2005
85,972
South Puget Sound, WA
:rolleyes::rolleyes::rolleyes: ;lol
 

kennyp2339

Minister of Fire
Feb 16, 2014
5,493
07462
Highbeam, you got begreen to post off-topic! You win the thread, and will accrue double Internet Points for the rest of the day! :)
Yessssssss! he's actually a human, I thought he was Siri of the woodstove world.
 

begreen

Mooderator
Staff member
Nov 18, 2005
85,972
South Puget Sound, WA
Mr Kenny, all your btus are belong to us... Have a nice day.
 
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Ashful

Minister of Fire
Mar 7, 2012
15,715
Philadelphia
Got one "dirty" BK running tonight. Spent the evening working outside at 49F, and it's headed to 42F, so sparking it up felt at least partially justified.
 

kennyp2339

Minister of Fire
Feb 16, 2014
5,493
07462
Got one "dirty" BK running tonight. Spent the evening working outside at 49F, and it's headed to 42F, so sparking it up felt at least partially justified.
Same here, I have the classic creosote V on my window
 

Highbeam

Minister of Fire
Dec 28, 2006
18,383
Mt. Rainier Foothills, WA
Got one "dirty" BK running tonight. Spent the evening working outside at 49F, and it's headed to 42F, so sparking it up felt at least partially justified.
We let the house cruise last night with no fire. Only down to 50 overnight. Been riding the rollercoaster of shoulder season here so far this fall. Burning up the less desirable, but very dry, wood I picked up this summer and split really big for low output burns.
 
Ahhhhh.......shoulder season. Interesting to see how others deal with it.

It's a bit tricky here in the hills of Colorado where the temps can...and sometimes do... swing 50 degrees in a day. (and it's only an 800 sq ft house)

With low temps routinely in the 20's.....we've been burning the Princess nightly for almost a month now. Unlike Highbeam, we burn smaller rounds at this time of year....usually juniper/cedar/oak/alder. It's the nuisance (2-3") stuff we've gathered taking down larger trees. Basically it's the material that...with my older (non-cat) stove....we wouldn't have even bothered with because it would have been no more than a flash in the pan. With the BK...we get great heat from this material for our overnight heating needs and a fire that doesn't run into mid day (and run us out of the house) the next day when the temps have risen substantially outside.

While I know this isn't the optimal way to operate these stoves....I'm sure we'll get around to full-time burns soon enough.

And yes....the glass is semi-black. I scrape the gunk off when I empty the ashes every few weeks or so...but other than that...we just ignore it.
 
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kennyp2339

Minister of Fire
Feb 16, 2014
5,493
07462
Don’t scrape the glass, just run the stove on high, I also feel your pain with temp swings, we were down to 34 this am, I foolishly loaded the stove up with ash and maple, the princess is set at 1 o’clock but with high solar gain and temps in the low 60’s I’m thinking that I will be opening some windows when I get home from work
 

Sconnie Burner

Feeling the Heat
Aug 23, 2014
488
Western Wi
If i had to choose between clean glass or catalytic eficiency, well come get my glass.
I'm with you on that one. I know I would be using twice the wood and dealing with lots of relights from the same size tube stove! (Burning with an Ideal Steel Hybrid). And holy man do I not miss the temp fluctuations we had with a non-cat. And plenty of large coals for a reload and go after 12 hrs.

I like the having flames when I want them and cat burn when I need a more even prolonged heating style. I actully get more heat out of a true cat burn (to be expected). When I let the secondaries burn the gases before they hit the cat my stove temps can be up to 100 degrees cooler.

As far as the glass goes 2 notches higher on the air setting and a full stove cycle and the glass will have just a thin white film on it with a little black on the bottom corners.
 
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Highbeam

Minister of Fire
Dec 28, 2006
18,383
Mt. Rainier Foothills, WA
Don’t scrape the glass, just run the stove on high,
That might work for some people but it absolutely does not work for all. Including me. I can run the princess at max setting for an hour with a full box of fuel and the shmuck stays on the window. It might be reduced some but it will NOT burn off.

It is much easier (and doesn't waste fuel or overheat the house) to just bust out the razor blade and scrape it off if you ever want to remember how a fully clean glass looks. At worst though, the glass only gets 50% covered with shmuck that you can't see fire through. Plenty of visible fire through the clear parts of the window.

I don't know of anybody that gets 100% blockage where they can't see fire at all. If there is someone that does, I would be doubting their fuel supply and operational procedures.
 

jetsam

Minister of Fire
Dec 12, 2015
4,962
Long Island, NY
youtu.be
I don't know of anybody that gets 100% blockage where they can't see fire at all. If there is someone that does, I would be doubting their fuel supply and operational procedures.
What! I always wring my splits out before I bring 'em inside. (Otherwise the wife is on me for all the water on the floor.)

One of these days I'm going to get tarzan to come over and wring out the whole tree for me before I cut it and split it!
 
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Highbeam

Minister of Fire
Dec 28, 2006
18,383
Mt. Rainier Foothills, WA
What! I always wring my splits out before I bring 'em inside. (Otherwise the wife is on me for all the water on the floor.)
I think you could probably mess up the glass and chimney really good by snuffing the cat and smoldering a cold fire. The active cat maintains heat for draft, a minimal amount of heat to keep the glass hot enough to remain cleanish. With a cold cat I'd bet even dry wood could make a mess.