2018-19 Blaze King Performance Thread Part 1 (Everything BK)

[Rickb]

I would think it would depend on the fan speed/heat transfer as to how much it would effect wood usage.

 

[chemie]

I would think it would depend on the fan speed/heat transfer as to how much it would effect wood usage.

I think we are talking about the low setting of the fan effect on wood consumption where it seems or experienced to have higher effect than when stove is running at mid or high setting with matching fan settings.

 

[Rickb]

Well I can say in my experience the fan on even on low has a pretty large effect.

I only run my fan on low, and I only do it for a 1-3 hour period depending on how cold it is in the room. If its cold outside(under 40f.), but above 70 inside I run my stove on low(low to me is turned down till it stops.). I get about 6 hours of heat from 3-4 splits.(1/4 - 1/3 full?). Same condition but colder inside so I run my fans on low and I get 4 hours of heat.

I only pack my stove full if its really cold outside and cold inside and I ussually run the fan 2 hours and its 8 - 12 hours of heat.

Just my experience for who ever cares.

 

[Ashful]

I think you can tell the difference by looking at the flue exhaust (until late in the burn, anyway)- if you see any smoke, the cat is off the job.

This may sometimes be the case, but it is not always true. I have seen smoke with an active cat, many times, on five different catalytic stoves. There is no guarantee you will have no smoke, just because the cat is active, nor does the presence of smoke indicate the cat has dropped.

 

[Diabel]

This may sometimes be the case, but it is not always true. I have seen smoke with an active cat, many times, on five different catalytic stoves. There is no guarantee you will have no smoke, just because the cat is active, nor does the presence of smoke indicate the cat has dropped.

So, why is that? On both of my stoves (different animals) I can have a full burn with zero smoke/plume and in the next reload (same wood pile splits) occasional (15min) visible smoke in the middle of the burn with cat very active.

Before I got the BK I thought...sure it has to be the loved here (bholler!) VC and it’s issues. But now on occasion I see it with the new Princess as well.

 

[kennyp2339]

So, why is that?

I would imagine a combination of many things we just wouldn't understand or can control, seasoned wood that may have a moisture bubble, different outside pressures from subtle wind shifts that may extract more heat from the stove before the t-stat can open and heat the fire box fully again, under performing cat, heavy off gassing firewood.. many many things, I know this much, I have a much cleaner burn with this stove vs my old us stove.

 

[kennyp2339]

I only run my fan on low,

The highest I ever go on my fan is 3/4 wide open, but most of the time on the lower than half side, I feel with that combination I get better heat extraction from the stove top (have convection deck) and I'm able to keep the t-stat just a click above half way and still maintain long burns on the coldest of days.

 

[Diabel]

before the t-stat can open and heat the fire box fully again

This might be it.

 

[estepracing]

If anyone has a King how low can you run your t-stat I know it will vary but I'm trying to get an idea... Thanks...

Blaze King King Parlor Wood Stove

 

[BKVP]

Does BK have any data about how much using fan would affect wood consumption? Is it as dramatic as jetsam experienced like %50 difference?

There’s no lab data. I know first hand my burn times are a bit shorter when using the fans. But considering all the variables that influence actual burn times, I could lay all the reduction on the use of the fans.

Strictly anecdotal findings from fellow users may be most helpful.

 

[jetsam]

I'd like to emphasize that my 50% is only at the very lowest burn that the stove can do, and I'd wager that I have my lowest-burn parameters figured out better than a casual burner would.

It makes only a small difference on medium-low settings, and I have no data on high settings because I've never tried it.

We should be able to get some more data points though, we have several PI owners on here.

It's probably best not to group freestanders, semiflush inserts, and flush inserts together when thinking about this question. As the stove loses surface area, the fan becomes a bigger percentage of its heat dissipation.

 

[estepracing]

There’s no lab data. I know first hand my burn times are a bit shorter when using the fans. But considering all the variables that influence actual burn times, I could lay all the reduction on the use of the fans.

Strictly anecdotal findings from fellow users may most helpful.

Ya I'm not running fans, this time of year it's all about keeping the chill out not really heating. So a nice dark window is all I was going for...

Blaze King King Parlor Wood Stove

 

[showrguy]

If anyone has a King how low can you run your t-stat I know it will vary but I'm trying to get an idea... Thanks...

Blaze King King Parlor Wood Stove

I dunno if My input will help you, but here it goes..
My stack is about 35 ' so I have way more draft than a shorter stack, last year I added a key damper, this year I added another key damper, so now I have two of em, and I'm still above what BK recommends as far as draft..

So far I can see an improvement from last year, as far as burn times, but, it's early in the heating season..

My average cruise is around the 3:15 mark on the t-stat, maybe a bit lower this year with the added damper... So far that's what I'm seeing..

I've cut my draft from .23-.26, to .08-.13 with a pair if dampers..

Wee will see, it's a learning experience, every install is different..

 

[lsucet]

What is the right way to measure the draft on a BK? How high on the stack do you insert the tubing? At what point of the burn is the right time of measure it as for BK specs? I ask cause I will like to measure the draft on my taller setup.

 

[showrguy]

What is the right way to measure the draft on a BK? How high on the stack do you insert the tubing? At what point of the burn is the right time of measure it as for BK specs? I ask cause I will like to measure the draft on my taller setup.

As per BKVP the testing/certification is done 30" from stove top, and you check it at full burn..
Hope that helps..

 

[Poindexter]

My experience is running the fan kit wide open on an AF 30 cuts the total burn time by about half, but it also gets twice as many BTUs into the envelope. Or the same number of BTUs in half the time...

Running all the same fuel, plain old Black and White spruce, I can get 24-30 hour burns at outdoor ambients in the +40dF to +50dF range, fans off and tstat at low or medium low, with a hot reload onto an active cat at the end.

At the other end of the scale, same fuel, at the sort of temperatures that make PETA executives think about wearing garments made of fur, with the fan kit on high I can burn a load of spruce down to a legitimate hot reload in four hours.

The three variables I recognize are 1) outdoor ambient, colder air = more draft -> faster burn, 2) thermostat setting on the stove, higher setting = faster burn and 3) fan use, higher fan setting = faster burn.

At the end of the burn, my stove has a dynamic range of 6 or 7 to 1. I can burn a load of fuel down in four hours, or twenty eight hours, the question is how many BTUs per hour do I want out of the stove into my home.

Juggling fan speed versus tstat setting takes experience. Running the fan speed more or less the same as the tstat setting is a fine place to start. Tstat on high, fans on high. Tstat on low, fans on low. Once you have a feel for that, sure, play with it. This is not a commandment delivered to Moses in stone, it is a suggestion.

In really cold weather by my standards, when I am also running a humidifier and a distillation plant to make water for the humidifier, fan noise off the BK is negligible. In "shoulder" season, down to maybe +10dF or so, sure, leave the fans off for the peace and quiet, but leave the humidifier and distiller off too so it counts.

In cold weather, I run my fan kit continuously. I don't care where the wife sets the fan speed, as long as she doesn't set it to "off." There is a thing on the hi-fi playing the Beethoven called a volume knob. It can be twisted.

 

[Ashful]

So, why is that? On both of my stoves (different animals) I can have a full burn with zero smoke/plume and in the next reload (same wood pile splits) occasional (15min) visible smoke in the middle of the burn with cat very active.

Before I got the BK I thought...sure it has to be the loved here (bholler!) VC and it’s issues. But now on occasion I see it with the new Princess as well.

There is a limited amount of fuel the combustor can process, for a given rate of flow through it. At some points during the burn, your wood is off-gassing more fuel than at other times.

My stack is about 35 ' so I have way more draft than a shorter stack, last year I added a key damper, this year I added another key damper, so now I have two of em, and I'm still above what BK recommends as far as draft..

I've cut my draft from .23-.26, to .08-.13 with a pair if dampers..

I’m in the same situation. But I also find that I can just about stall it if I dial down to 0.06” WC (essentially completely closed key damper) during bypass mode. We could almost use a whole other thread to discuss the world of running key dampers and draft gauges on BK’s.

What is the right way to measure the draft on a BK? How high on the stack do you insert the tubing? At what point of the burn is the right time of measure it as for BK specs? I ask cause I will like to measure the draft on my taller setup.

I prefer the Magnehelic, it’s an old standard in the HVAC industry. There are many other types of manometer on the market, but I believe the Magnehelic is the best option, for this application.

Get some small stainless tubing, like 1/16” ID x 3/16” OD. Drill a corresponding hole in your stovepipe somewhere above the stove but below the key damper, preferably spaced well from either (to avoid localized pressure zones), and install the stainless tubing in the hole, fastening it to the pipe with tubing or wiring clamps. Then run a high-temp hose from Magnehelic to this pipe. I have a thread showing my rig, somewhere on this forum, maybe in one of last year’s four BK Performance threads.

 

[Ashful]

My experience is running the fan kit wide open on an AF 30 cuts the total burn time by about half, but it also gets twice as many BTUs into the envelope. Or the same number of BTUs in half the time...

... for the same thermostat setting? I still don’t understand why lowering the thermostat to compensate for the effect the fan introduces to the thermostat, doesn’t at least mostly compensate for having it running.

Of course, you could then argue that there’s no reason to run the fans if you’re just going to be cranking the stove down lower, but I’m talking principles here. The fan cools the thermostat, which causes it to open wider, for a given setting. Turning the knob lower should compensate, the way the thermostat works.

 

[jetsam]

The three variables I recognize are 1) outdoor ambient, colder air = more draft -> faster burn, 2) thermostat setting on the stove, higher setting = faster burn and 3) fan use, higher fan setting = faster burn.

I would add initial stove state and fuel MC to the list, but draft/thermostat/fan are all bigger variables.

 

[jetsam]

... for the same thermostat setting? I still don’t understand why lowering the thermostat to compensate for the effect the fan introduces to the thermostat, doesn’t at least mostly compensate for having it running.

Of course, you could then argue that there’s no reason to run the fans if you’re just going to be cranking the stove down lower, but I’m talking principles here. The fan cools the thermostat, which causes it to open wider, for a given setting. Turning the knob lower should compensate, the way the thermostat works.

Agreed, but that doesn't scale down to minimum burn settings. At the lowest burn you can do without the cat going out, turning the thermostat down and the fan on just puts the cat out.

I keep harping on this minimum burn thing because that's where my stove runs for 2-3 months of the year.

 

[mcdeadstein]

Agreed, but that doesn't scale down to minimum burn settings. At the lowest burn you can do without the cat going out, turning the thermostat down and the fan on just puts the cat out.

I keep harping on this minimum burn thing because that's where my stove runs for 2-3 months of the year.

I'm not an experience burner but this info is very helpful. I was under the impression I might be able to run the stove on "low" for 16-24 hours but my interpretation of low was both low-thermostat and low-fans. It is just good to know, because it is not spelled out in the manual. I would have been frustrated if I had tried for long burns and never got them because I was always running the fans.

Granted, it is relative to BK stoves. 8-12 hour burns with fans on is still plenty for me.

 

[chemie]

I'm not an experience burner but this info is very helpful. I was under the impression I might be able to run the stove on "low" for 16-24 hours but my interpretation of low was both low-thermostat and low-fans. It is just good to know, because it is not spelled out in the manual. I would have been frustrated if I had tried for long burns and never got them because I was always running the fans.

Granted, it is relative to BK stoves. 8-12 hour burns with fans on is still plenty for me.

I am in the same boat. I was assuming that low burn times advertised or mentioned included fan on. Manual only says use fan low with low setting, fan high with high settings. Nothing about shortening burn time if the fans on.

 

[Ashful]

I wouldn’t sweat it, @chemie. I turned my fans on last night with my first fires of the year, and I won’t turn them off until next May, and I’m still exceeding BK’s advertised burn times by more than 20%. I have no doubt, that with good hardwoods, you will be able to do the same, even with the fans running on a low setting.

And, I believe @jetsam, but then I also have no reason to run the fans above a very low setting when I’m running at minimum burn rate.

 

[lsucet]

I think for experience that with fan on, on low as this is the way that i use them when need it, i can dial the thermostat lower to compensate. The wood consumption is faster than with them off but not to take into account if you also find the compensation setting. maybe 10-20%? you kill the probe into the inactive zone but cause of the low heat on top, the thermostat opens and the cat still producing heat.
After all is the cat that heat the stove that the other way around. that is why if you shut the fans the probe goes up into the active zone. my experience by the way.

 

[Poindexter]

I would add initial stove state and fuel MC to the list, but draft/thermostat/fan are all bigger variables.

Correct, but I specified hot reloads and same fuel ;-)

A common setting for us is tstat on high and fan kit on medium. I rarely run high/high, it is a setting mostly reserved for warming the house up after work before the wife gets home, or bitterly cold weather.

With my install, I find it is more time efficient for me to choose a combination as I leave for work that gives me an active cat and a decent coals bed when I get home. I would rather have the house a few degrees cooler with the stove ready for a hot reload, compared to having the house at a specific temp but the combustor cold and no coals to use.

I will often choose medium low tstat and low fans for work day, and meet the conditions above.

My own hypothesis is the fan kit pulls heat off the top off the steel firebox, right out of the cat, pushes it out in the room and the thermostat opens to maintain the set temp, compared to the fans being not used.