2019-20 Blaze King Performance Thread Part 1 (Everything BK)

MissMac

Minister of Fire
Dec 4, 2017
567
NW Ontario
What is the proper way to do it? On a reload with the bypass open, aren't you suppose to let the box warm up for 10-15? If it's already raging hot, do you close the bypass right away on a reload? I guess I thought large flames were ok as the flame shield should protect the cat, right? What am I missing?
MacinJosh, just follow the instructions in your stove manual. This is fool proof. The majority of fellows on here are super stove enthusiasts, and like to tinker and tweak - but most importantly, they have the knowledge and skills and experience to do this. As you're learning your stove, the best way to do that is to follow the manufacturer's instructions. Then, some day you too may decide to start tweaking things as you learn what your stove likes/dislikes, and how to get the repeatable performance/results out of it that you want. Try keeping a journal - i did that my first year, and it really helped me dial the stove in so that i knew exactly what to do at what time with what wood under a specific set of conditions/coals etc. to get optimal and predictable and repeatable performance.
 

spudman99

Feeling the Heat
Jan 26, 2018
317
Yardley, PA
Noob question alert:

What exactly is the purpose of a "burn-in". I know what it is, I do it, I just don't know the technical reason or why it is beneficial to a BK stove? This is an informational question, not one to solve a problem.

Sometimes I am reloading a pretty warm stove, cat in the halfway active range or 12:00. Plenty of coals and some split carcasses remaining, first open bypass for 2-3 min. Thermo on high. Open door really slow, to allow air to go up flue first. I then rake coals a bit, add the required splits and close door. Let the flames catch with bypass open. Then close bypass since it is active, let burn on high for maybe 10 min, sometimes less but always with at least half the load in flames. Turn thermostat down to low since I wont be back for 12 hours.

I clearly am not doing a 20 min char, nor am I allowing the bypass open for an extended time. Circle back to my original question as to what sequence is optimal for the operation of this insert. Thanks in advance.
 
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jetsam

Minister of Fire
Dec 12, 2015
4,656
Long Island, NY
youtu.be
Noob question alert:

What exactly is the purpose of a "burn-in". I know what it is, I do it, I just don't know the technical reason or why it is beneficial to a BK stove? This is an informational question, not one to solve a problem.

Sometimes I am reloading a pretty warm stove, cat in the halfway active range or 12:00. Plenty of coals and some split carcasses remaining, first open bypass for 2-3 min. Thermo on high. Open door really slow, to allow air to go up flue first. I then rake coals a bit, add the required splits and close door. Let the flames catch with bypass open. Then close bypass since it is active, let burn on high for maybe 10 min, sometimes less but always with at least half the load in flames. Turn thermostat down to low since I wont be back for 12 hours.

I clearly am not doing a 20 min char, nor am I allowing the bypass open for an extended time. Circle back to my original question as to what sequence is optimal for the operation of this insert. Thanks in advance.
Optimal for a new operator is what the manual says.

An experienced operator will approach the question knowing what their flue and firebox temps are like at the start of the burn, what the dryness of their wood is like, what the BTU needs will be from this load, exactly how high they plans to burn it, what his draft will be like for the time period of the burn, and what the split size and fuel type will be. Throw all that at a guy with a new stove and he's likely to think it's too complicated. I assure you that it's not hard, and you won't need a calculator. But you will treat stove routines differently as you learn the things that make the stove work.

The goals are to keep the top of the flue above 250°, keep the cat above 500°, and to provide the desired heat output for the desired burn time (this is often a compromise in cold weather if the stove's your only heat source and you need the be out or asleep for 12 hours+).

Practical examples: I might burn on high for an hour or more in the (extremely unlikely) event that I was doing a cold start with wet wood. For a winter reload, with nice dry room temp wood going into a hot stove, it gets no time at all on high. For a shoulder season reload, at the end of a 16-20 hour burn, I need to bring things back up to temp, so it does burn on high to warm up the flue, cat, and stove.
 
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TheIglu

Member
Nov 17, 2008
30
Royalston, MA
Cleaned my chimney last weekend after burning for a couple months with the new stove( Princess Ultra). 19' of stainless chimney, nearly straight up. Barely 1/4 cup of gunk.

And I thought for sure I would of gummed it up pretty good with how low I run the stove most of the time.

God I love this stove.
 

Ashful

Minister of Fire
Mar 7, 2012
15,438
Philadelphia
I currently have my door open like the other guy trying to burn coals down.
You’d do better to rake the coals forward, throw two splits atop them, and run in wide-open throttle with bypass closed.
What do the BK's come with? Steel or ceramic?
You sure about that, Steve? As of last year, the Princess and King were still shipping with ceramic. The 20’s and 30’s have been Steel for many years, though
Noob question alert:

What exactly is the purpose of a "burn-in". I know what it is, I do it, I just don't know the technical reason or why it is beneficial to a BK stove?
1. Baking moisture out of wood so you don’t stall the cat when you subsequently turn down low.
2. Burn off the creo deposits that are left in your firebox from the prior low burn cycle, and limit accumulation.
 

MacinJosh

Feeling the Heat
Mar 4, 2015
282
Crestwood, KY
If you're always going to burn on high, there's not much point to spending the extra on a BK unless you are worried about overfires and want the thermostatic protection.

I went BK because I want long-ass low burns, and it is sure good at that. (And it does fine at high burns, too. Mine even does high burns without coal problems, because I feed it pine! :))
Same, it's 16 degrees here so this day was not the norm. The ville hangs around 30-40 for most the winter so long slow burns is exactly what I was after. I'm just learning as I go here and soliciting all the good info I can get from y'all along the way. During these cold snaps though, I need more BTUs and the coaling effect seems to be in high gear.
 

AlbergSteve

Minister of Fire
Dec 11, 2017
751
Vancouver Island
You sure about that, Steve? As of last year, the Princess and King were still shipping with ceramic. The 20’s and 30’s have been Steel for many years, though
My bad, my brain skimmed the question. I was thinking Ashford. Yes, the 20 and 30 boxes come with steel.
 
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Ashful

Minister of Fire
Mar 7, 2012
15,438
Philadelphia
Yeah, I put the flame to the new load for a while with bypass open, like you say for 10-15 min, with a pretty lively fire. Then I cut the air and let the flame die back for a couple min before closing the bypass.
Ok, that's the part I was missing. Thank you!
Note that Woody’s setup may require this, but that may be unique to his setup (strong draft?) or his stove, which is a Woodstock. I also used to sometimes do this on one of my Ashfords, waiting for the probe to read active on 30’ tall un-moderated chimney, but a key damper solved that problem more properly.

Moreover, I’ve learned you do not need to wait even one quarter the amount of time it takes to reach active cat, before closing that bypass. Here is where my cat probe and pipe thermo we’re sitting when I closed the bypass on last evening’s reload on almost-dead coals:

59E34A62-F368-4627-803B-EC23B6D387D5.jpeg
C208FE03-4AC2-4A3F-8462-E66B118DB2C9.jpeg

... and the cat started glowing almost immediately, indicating it was ready to go, despite the probe thermometer reading almost dead-cold.

AA6E8151-B46C-47B9-8D7C-29CD9CA77B43.jpeg

If you’re sitting and waiting for a too-slow probe to tell you to close the bypass, while your fire is raging so furiously that you need to turn down the air, you’re just wasting fuel. That probe tells you what the cat was doing more than ten minutes ago, which is better than nothing, but it’s a lot like driving by only looking at the rear-view mirror.

... and before anyone asks, yes my thermometer is calibrated at room temp. And yes, I do this on two different Ashfords on two vastly different chimney systems, it’s not something unique to this setup.
 
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Woody Stover

Minister of Fire
Dec 25, 2010
11,850
Southern IN
Note that Woody’s setup may require this, but that may be unique to his setup (strong draft?) or his stove, which is a Woodstock. I also used to sometimes do this on one of my Ashfords, waiting for the probe to read active
My stove breathes well but I have just 16' of stack, so draft isn't excessive. I don't have a probe on my stove right now, I may do that at some point. I'm going by flue temps, or I know that if the stove top's at 150, the cat will glow immediately. Now, my cat might have about three years on it..my present instant-glow settings will change if I slap a new cat in there.
 
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BKVP

Minister of Fire
Note that Woody’s setup may require this, but that may be unique to his setup (strong draft?) or his stove, which is a Woodstock. I also used to sometimes do this on one of my Ashfords, waiting for the probe to read active on 30’ tall un-moderated chimney, but a key damper solved that problem more properly.

Moreover, I’ve learned you do not need to wait even one quarter the amount of time it takes to reach active cat, before closing that bypass. Here is where my cat probe and pipe thermo we’re sitting when I closed the bypass on last evening’s reload on almost-dead coals:

View attachment 255649
View attachment 255651

... and the cat started glowing almost immediately, indicating it was ready to go, despite the probe thermometer reading almost dead-cold.

View attachment 255652

If you’re sitting and waiting for a too-slow probe to tell you to close the bypass, while your fire is raging so furiously that you need to turn down the air, you’re just wasting fuel. That probe tells you what the cat was doing more than ten minutes ago, which is better than nothing, but it’s a lot like driving by only looking at the rear-view mirror.

... and before anyone asks, yes my thermometer is calibrated at room temp. And yes, I do this on two different Ashfords on two vastly different chimney systems, it’s not something unique to this setup.
I have posted previously the cat therms are latent in response and not highly accurate. In fact, closing the bypass actually directs gases to the combustor....so once the needle begins to move, closing the bypass accelerates needle movement.

This is going to be install specific on when that can be done due to many variables including moisture content.
 

Rob711

Feeling the Heat
Oct 19, 2017
318
Long Island, ny
what badness occurs with premature bypassing? assuming dry wood. And thermostat on high
 
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Holiday

Burning Hunk
Feb 18, 2013
190
Saskatchewan, Canada
Was wondering that too, if you close the bypass too early so it's going through the cat on a stove that you know is getting hotter.
 
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Ashful

Minister of Fire
Mar 7, 2012
15,438
Philadelphia
what badness occurs with premature bypassing? assuming dry wood. And thermostat on high
If you close it way early, you’ll find the fire begins to wane, and may either stall out completely or take a ridiculous amount of time to reach active. During this time, you’re just passing all of those creo-causing volatiles thru the combustor and your chimney pipe. So, the once or twice I’ve closed the damper early and found the cat wasn’t glowing within 2 minutes (it’s usually more like 20 seconds), I just go back to bypass and wait another five minutes.

I’m not suggesting anyone close the bypass before the combustor is ready to take off. Rather, I’m saying your combustor is likely ready to take off long before the probe indicates it is. Anyone who runs one of these stoves on a daily basis for more than a few weeks will quickly learn when it is ready to go by the look of the fire, without having to wait for a probe to tell you.

The first two indicators anyone can judge are:

1. Flame is healthy and vigorous.
2. Wood load is completely charred over.
 
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MacinJosh

Feeling the Heat
Mar 4, 2015
282
Crestwood, KY
Note that Woody’s setup may require this, but that may be unique to his setup (strong draft?) or his stove, which is a Woodstock. I also used to sometimes do this on one of my Ashfords, waiting for the probe to read active on 30’ tall un-moderated chimney, but a key damper solved that problem more properly.

Moreover, I’ve learned you do not need to wait even one quarter the amount of time it takes to reach active cat, before closing that bypass. Here is where my cat probe and pipe thermo we’re sitting when I closed the bypass on last evening’s reload on almost-dead coals:

View attachment 255649
View attachment 255651

... and the cat started glowing almost immediately, indicating it was ready to go, despite the probe thermometer reading almost dead-cold.

View attachment 255652

If you’re sitting and waiting for a too-slow probe to tell you to close the bypass, while your fire is raging so furiously that you need to turn down the air, you’re just wasting fuel. That probe tells you what the cat was doing more than ten minutes ago, which is better than nothing, but it’s a lot like driving by only looking at the rear-view mirror.

... and before anyone asks, yes my thermometer is calibrated at room temp. And yes, I do this on two different Ashfords on two vastly different chimney systems, it’s not something unique to this setup.
Good info, thanks! Curious, do you let thew new reload burn in for awhile with the bypass open and therm on high just to burn off any possible moisture, etc. before closing the bypass? I do believe this is what the instructions say. Therefore, I do this not because I don't have an active cat, but more because the instructions tell me to. Thoughts?
 

Tron

Member
Jan 1, 2020
75
Jackson MS
Sounds reasonable to let the combustion gases get up to temperature first. On a fresh reload, even with the cat active, I doubt the gases are hot enough right away.
 

MacinJosh

Feeling the Heat
Mar 4, 2015
282
Crestwood, KY
I have posted previously the cat therms are latent in response and not highly accurate. In fact, closing the bypass actually directs gases to the combustor....so once the needle begins to move, closing the bypass accelerates needle movement.

This is going to be install specific on when that can be done due to many variables including moisture content.
So here is the dumb question.....what happens if you close a bypass BEFORE the cat is up to temp? Obviously no catalytic reaction will occur but can the cat get damaged? If so, I guess my knee jerk thought would be to error on the side of caution and wait until that probe says good to go, no?

*EDIT* Read a little further and got my answer.
 

jetsam

Minister of Fire
Dec 12, 2015
4,656
Long Island, NY
youtu.be
I may stick with steel cats from here on out, just because it simplified my wife's stove reloading instructions (she only loads it once or twice a year
If you close it way early, you’ll find the fire begins to wane, and may either stall out completely or take a ridiculous amount of time to reach active. During this time, you’re just passing all of those creo-causing volatiles thru the combustor and your chimney pipe. So, the once or twice I’ve closed the damper early and found the cat wasn’t glowing within 2 minutes (it’s usually more like 20 seconds), I just go back to bypass and wait another five minutes.

I’m not suggesting anyone close the bypass before the combustor is ready to take off. Rather, I’m saying your combustor is likely ready to take off long before the probe indicates it is. Anyone who runs one of these stoves on a daily basis for more than a few weeks will quickly learn when it is ready to go by the look of the fire, without having to wait for a probe to tell you.

The first two indicators anyone can judge are:

1. Flame is healthy and vigorous.
2. Wood load is completely charred over.
I close mine way before the load is charred. Usually as soon as the door is closed on a winter (hot stove) reload, now that I have a steel cat. Only time I wait around to put the cat in is on a cold start which is only a couple times a year- and I question whether that's even needed. Obviously you're in trouble if you somehow completely mask your cat with creosote, but partial masking will just burn off again. I've never seen a fleck on mine.

I disagree that putting the cat in will knock the flames down. If you flip the cat in and there is an immediate change in your firebox, you have a plugged cat.
 

Woody Stover

Minister of Fire
Dec 25, 2010
11,850
Southern IN
do you let thew new reload burn in for awhile with the bypass open and therm on high just to burn off any possible moisture, etc. before closing the bypass? I do believe this is what the instructions say.
I've read here that damage of the bypass gasket retainer can occur if the stove is fired too hard, for too long, with the bypass open. I think that affects only certain models though, I'm not sure.
I don't doubt that most stove makers stress burning in the load a bit in bypass, since most folks aren't going to have optimally dry wood, and the cat is more prone to crash if some of the moisture isn't burned out of the wood first .
Doesn't the manual say to burn on high for a while after you close the bypass? I'd guess that's to make sure the burn doesn't crash if the wood isn't real dry, and also to try to burn wet creo off the inside of the box.
what badness occurs with premature bypassing? assuming dry wood. And thermostat on high
I don't know if my theory holds much water, but I figured that if you run creo through a cat that's not burning yet, wet creo may be deposited on the cat cell walls. When the cat finally burns that wet stuff, I think the residue could get baked onto the walls, masking the catalytic surface and not able to be easily blown out, like regular fly ash is.
Note that Woody’s setup may require this, but that may be unique to his setup...or his stove,
Yep, I'd think stove design comes into play as well. With a lot of stone mass to heat up to light-off temp, my stove is going to require a more time to attain that temp. Of course, it's possible to toss a lot of flame heat to the cat and light it before the stove is really up to temp, but if you try to cut the air at that point the cat will crash.
Conversely, the BK design appears to me to concentrate heat inside the stove, maybe to allow a long, low burn while still keeping the cat active (hot enough.) The baffles inside the box keep heat in, as do the external heat shields, which I noticed are not open at the top on the Princess and King. Other stoves I've seen have the tops of the side shields open so that air can convect up between the firebox wall and the shield, stripping heat off the box and dumping it into the room. And the thin steel of the BK doesn't have as much thermal mass to heat.
Disclaimer: Hey, I ain't no rocket stove scientist.. ;lol
 

spudman99

Feeling the Heat
Jan 26, 2018
317
Yardley, PA
Completely off topic, but I was in Walmart yesterday and in an aisle display had Distilled gallon jugs of water for $0.62 each. If anyone is planning on doing a vinegar bath this spring, might be a good time to grab a few bottles. YMMV
 

Woody Stover

Minister of Fire
Dec 25, 2010
11,850
Southern IN
Completely off topic, but I was in Walmart yesterday and in an aisle display had Distilled gallon jugs of water for $0.62 each. If anyone is planning on doing a vinegar bath this spring, might be a good time to grab a few bottles. YMMV
And for the wash or simmer they also specify distilled vinegar, though I'm not sure why..
 

Tron

Member
Jan 1, 2020
75
Jackson MS
And for the wash or simmer they also specify distilled vinegar, though I'm not sure why..
That's because you don't want anything on the cat that does not evaporate off and could char when fired up. So using balsamico vinegar is a bad idea.
From a chemist's perspective: pure vinegar is just a 10% solution of acetic acid in water, nothing else. So you could buy 50% acetic acid, dilute it 1:10 and have the same acid concentration as a 1:1 vinegar/water mixture.