2017-18 Blaze King Performance Thread PART 2 (Everything BK)

[aaronk25]

That sounds iffy. Now we're saying the stove is at positive pressure versus the room, which seems unlikely, since the stove is drawing from the room to fill the vacuum in the flue. Take the door gasket away and you'll get much increased airflow, not reverse airflow. I understand intske air is getting dragged across the door, but a porous gasket is going to drag air in, not out (unless the fire is out, and then I guess it's more open to debate).

Except.....that air if air is going directly off the airwash, it is very turbulent and creates vortices that extend down the face of the glass. Pulsing/turbulent air create a hammering action that drives that stinky creosote though the gasket, and then the hot knife edge bakes it and turns it into smoke which stinks.

The time in which the stove makes the most stink is when going from high to low. If the draft was at .12 on high when the t stat is closed the pressure drop goes to .17 as the chimney is hot and sucking really hard against the closed thermostat. Over a period of time say 20 mins the chimney cools to its cruise temp and I see the manometer drop to .1 or lower and smell goes down as draft goes down. This is why I think a lot of us have been chasing the problem in the wrong direction.


I think a good design change would be a thermal break at the knife edge so the gasket isn’t contacting such a hot surface than can re burn leached creosote.


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[aaronk25]

That angled air wash is supposed to perform like a Airplane wing, but it’s not shaped like one and as soon as the angle of attack is increased by creating negative pressure right behind it the air stalls and jack hammers all over the place.

All I can say is if I use a key damper and set the T-stat to a higher setting there is little or zero smell and the glass stays really clean and if I open the key damper up and back the T-Stat down to 2:30 o’clock position I smell stink and the glass gets a dark V shape of creosote on it.




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[Highbeam]

Lets not forget that the fuel load is causing an expansion and increased pressure as it ignites and heats the intake air. It’s not correct to assume negative pressure in all parts of the firebox just because on average air is being drawn into the stove.

I wonder if bkvp has ever tested his draft strength? Does it hit that very low bk spec?

 

[webby3650]

Not sure if this is the same issue, but when i have my bypass open and air control on max setting to burn in a new load of wood i get smoke puffing out of all my connector pipe seams, if i turn down the air to around 2.5 and the smoke stops puffing out of the seams.

Totally different issue. You have some issue with your chimney that’s preventing smoke from getting out of the flue quick enough. Too many bends, long horizontal run, clogged cap, basement Tee system... etc...

 

[Ashful]

That sounds iffy. Now we're saying the stove is at positive pressure versus the room, which seems unlikely, since the stove is drawing from the room to fill the vacuum in the flue. Take the door gasket away and you'll get much increased airflow, not reverse airflow. I understand intske air is getting dragged across the door, but a porous gasket is going to drag air in, not out (unless the fire is out, and then I guess it's more open to debate).

In a dynamic system, it's normal to have varying pressures, such that one area of the system could see positive pressure while the net system is at negative pressure. Now, in a big open cavern like a firebox, it doesn't seem intuitive we could have a localized high pressure while the box is net negative. However, I've seen the vigor with which my air wash works, so based on that, it seems plausible.

Is Chris (BKVP) chiming in on ths potential smoke issue at all? I believe he was dealing with some of the members on a individual basis (private chats).

It would be nice if he could shed some light on this issue here, so potential new buyers would be at somewhat ease.....

As with all such issues, I suspect he sees it best to not participate in the speculation, and wait until they have a proven answer. Better yet, a proven solution. It helps to avoid those inevitable, "but you said..." situations that manufacturers find themselves in.

That angled air wash is supposed to perform like a Airplane wing, but it’s not shaped like one and as soon as the angle of attack is increased by creating negative pressure right behind it the air stalls and jack hammers all over the place.

All I can say is if I use a key damper and set the T-stat to a higher setting there is little or zero smell and the glass stays really clean and if I open the key damper up and back the T-Stat down to 2:30 o’clock position I smell stink and the glass gets a dark V shape of creosote on it.

At what height do you have your manometer on the flue? I see myself putting a key damper above the manometer, so that I can tune it to the day's weather. With the EPA testing done 48" off the stove, or even with BKVP's suggested compromise of 24", that would put the key damper much higher than I'd like it.

 

[AlbergSteve]

Is Chris (BKVP) chiming in on ths potential smoke issue at all? I believe he was dealing with some of the members on a individual basis (private chats).

It would be nice if he could shed some light on this issue here, so potential new buyers would be at somewhat ease.....

He's working on it...

 

[AlbergSteve]

@AlbergSteve, 6" rear clearance from the heat shield to the wall.

Here's the clearance chart for the Princess. Our situation is the fourth row down: roof exit, close clearance. We don't need side shields because we have plenty of clearance on either side. We do have the proprietary heat shield on the back.

Scroll down to page 14 for the chart.

(broken link removed to https://www.blazeking.com/EN/PDF/manuals/OM-PE-E.pdf)

Thanks @becasunshine . I didn't realize in the case of the Princesess's the clearances are reduced with the shields/fans. With the 20/30 boxes there are no reductions with the optional shields/fans - they are only required if they're placed in and alcove or corner... and the Ashford's don't have an optional shield at all.

 

[DuaeGuttae]

Is Chris (BKVP) chiming in on ths potential smoke issue at all? I believe he was dealing with some of the members on a individual basis (private chats).

It would be nice if he could shed some light on this issue here, so potential new buyers would be at somewhat ease.....

See post #771 of this thread. It doesn’t get into speculation on problems which is probably best, but it’s clear that BK is addressing it. I also sent him a message last spring privately as a potential customer, and he responded with the information I needed. I’m sure he would be glad to address any specific questions about your potential setup.

 

[kf6hap]

Sans the flapper, this might be a nice suction intake terminal (provided it is above the snow line).


(broken link removed)

 

[aaronk25]

In a dynamic system, it's normal to have varying pressures, such that one area of the system could see positive pressure while the net system is at negative pressure. Now, in a big open cavern like a firebox, it doesn't seem intuitive we could have a localized high pressure while the box is net negative. However, I've seen the vigor with which my air wash works, so based on that, it seems plausible.


As with all such issues, I suspect he sees it best to not participate in the speculation, and wait until they have a proven answer. Better yet, a proven solution. It helps to avoid those inevitable, "but you said..." situations that manufacturers find themselves in.


At what height do you have your manometer on the flue? I see myself putting a key damper above the manometer, so that I can tune it to the day's weather. With the EPA testing done 48" off the stove, or even with BKVP's suggested compromise of 24", that would put the key damper much higher than I'd like it.

Key damper is on the stove as that is what the install manual called for and to top it off the key damper is the Selkirk line was the best fitting stove adapter offered for the blaze king.

Manometer is pulled from the cat thermometer hole, but I checked wide open draft at 18” above stove though flue temp probe hole and the though cat hole and both were exactly the same. If like to add another key damper up higher in order to drop the flue vacuum in steps instead of all at once to reduce inline turbulence (not sure if that will matter).


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[Diabel]

See post #771 of this thread. It doesn’t get into speculation on problems which is probably best, but it’s clear that BK is addressing it. I also sent him a message last spring privately as a potential customer, and he responded with the information I needed. I’m sure he would be glad to address any specific questions about your potential setup.

Thank you.

 

[kennyp2339]

At what height do you have your manometer on the flue? I see myself putting a key damper above the manometer, so that I can tune it to the day's weather. With the EPA testing done 48" off the stove, or even with BKVP's suggested compromise of 24", that would put the key damper much higher than I'd like it.

I'm running my draft test drilling a hole about 24" in the black pipe from stove top. My existing damper is about 14" from the stove top.
The new dvl I have that I will be install afterwards regardless of draft outcome, it has the damper in the flue collar adapter, then I have a piece of adjustable dvl, then the ceiling support box adapter.
I don't think it matters where you install the damper, the reason why so many stove instructions say to install it higher is to keep it out of reach from children, other than that it shouldn't matter where its located.

 

[Ashful]

I'm running my draft test drilling a hole about 24" in the black pipe from stove top. My existing damper is about 14" from the stove top.
The new dvl I have that I will be install afterwards regardless of draft outcome, it has the damper in the flue collar adapter, then I have a piece of adjustable dvl, then the ceiling support box adapter.
I don't think it matters where you install the damper, the reason why so many stove instructions say to install it higher is to keep it out of reach from children, other than that it shouldn't matter where its located.

Your manometer is above your damper? How do you see the effect that damper adjustments have on your draft?

 

[tarzan]

Your manometer is above your damper? How do you see the effect that damper adjustments have on your draft?

Unless there's leaks, draft should remain constant on either side of the damper shouldn't it?

 

[SuperJ]

Unless there's leaks, draft should remain constant on either side of the damper shouldn't it?

Flow will be the same but the pressure will certainly be different. Any restriction is going to cause a change in pressure.

 

[aaronk25]

Unless there's leaks, draft should remain constant on either side of the damper shouldn't it?

Greatest pressure drop will always be on the side above the damper. As the chimney will be sucking against the damper. In order to have equal pressure the chimney would have to cool to a point that would only produce a matched amount of vacuum.





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[tarzan]

Yeah, I was thinking in terms of flow, not pressure

 

[aaronk25]

Yeah, I was thinking in terms of flow, not pressure

Oh ya, sorry your spot on then!


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[tarzan]

Oh ya, sorry your spot on then!


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No, I got confused. I was thinking in terms of velocity when the question was about pressure.

 

[MissMac]

That angled air wash is supposed to perform like a Airplane wing, but it’s not shaped like one and as soon as the angle of attack is increased by creating negative pressure right behind it the air stalls and jack hammers all over the place.

All I can say is if I use a key damper and set the T-stat to a higher setting there is little or zero smell and the glass stays really clean and if I open the key damper up and back the T-Stat down to 2:30 o’clock position I smell stink and the glass gets a dark V shape of creosote on it.




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I don’t have a damper, but like you I have nice clean glass and no smell on a high t-stat setting. And also similar to you, when I back down the t-stat, i get the smell. So how are you saying that the damper is eliminating the smell on a lower setting for you?

 

[kennyp2339]

LOL I see the issue, I'll just drill a little lower on the black pipe for the manometer while testing, fyi I wont know actual data when I switch to dvl, I'm not drilling any holes in that pipe, all my testing will be done with my cheap single wall pipe. I just want to see if I'm over the top with the draft, I have a feeling I am, I just want to confirm it 1st.

 

[MissMac]

LOL I see the issue, I'll just drill a little lower on the black pipe for the manometer while testing, fyi I wont know actual data when I switch to dvl, I'm not drilling any holes in that pipe, all my testing will be done with my cheap single wall pipe. I just want to see if I'm over the top with the draft, I have a feeling I am, I just want to confirm it 1st.

I don’t know much about dampers with regards to using them with BKs, but I’m curious how you’ll use yours without having some sort of manometer permanently integrated into your system - how do you use a damper on these stoves appropriately if you don’t have real-time draft info?

Also curious how many of your BK enthusiasts have dampers in your system?

 

[kennyp2339]

My idea is simple, run the stove at high with the existing damper open and take a reading, see what the meter reads, next close the damper and see the difference, all the while look at the fire behavior.
The rest is off the cuff... I’m just trying to slow my burns down some, I should be getting 6-8hrs on high, I can only accomplish that now with the damper, I just want to back this up with readings.

 

[tarzan]

I don’t know much about dampers with regards to using them with BKs, but I’m curious how you’ll use yours without having some sort of manometer permanently integrated into your system - how do you use a damper on these stoves appropriately if you don’t have real-time draft info?

Also curious how many of your BK enthusiasts have dampers in your system?

I've burned wood and coal in many different stoves, some with dampers, others not. I don't need a damper with the BK. It is the most controllable and predictable stove I have ever ran, period. No need for a damper on my setup.

 

[MissMac]

My idea is simple, run the stove at high with the existing damper open and take a reading, see what the meter reads, next close the damper and see the difference, all the while look at the fire behavior.
The rest is off the cuff... I’m just trying to slow my burns down some, I should be getting 6-8hrs on high, I can only accomplish that now with the damper, I just want to back this up with readings.

Oh okay, thanks for the info. What kind of wood do you burn out of curiousity? 6-8 on high sounds pretty good to me, but then again, I’m burning jack pine. Burning some of those wonderful hardwoods you guys have down south, what kind of burn times can you get on wide open?