When to reduce air, to burn "longer"

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Prometeo

Minister of Fire
Jan 7, 2022
640
IT
HI, I would like some advice what is the most appropriate procedure to start closing the air, in relation to the temperature of the stove, or flue ? How do you do it? Is it normal for the flue to start making a little smoke, reducing the air?
 
What type of stove do you have?

With my PE, I start cutting the air down to 1/2 way once the insert fan kicks on from a cold start, then shut it down slowly as the stove temps go up.

With the 13 (freestanding) , I check secondaries, and thermometer readings.
 
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What type of stove do you have?

With my PE, I start cutting the air down to 1/2 way once the insert fan kicks on from a cold start, then shut it down slowly as the stove temps go up.

With the 13 (freestanding) , I check secondaries, and thermometer readings.
Thank you, I have a jotul f 500 has a vermiculite baffle, it has no air hoses, air comes from behind, like F400. How many degrees does your fan start?
 
I would honestly just experiment with it. If you turn air down and it almost puts the fire out, then wait a bit to turn air down.
How dry is your wood?
 
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Thank you, I have a jotul f 500 has a vermiculite baffle, it has no air hoses, air comes from behind, like F400. How many degrees does your fan start?
We don't know anything about that version of the f500 so it's pretty hard to give advice
 
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I would honestly just experiment with it. If you turn air down and it almost puts the fire out, then wait a bit to turn air down.
How dry is your wood?
this year I had very old wood, mixed, 15 percent and elm a little tall unfortunately, even 25, I only put a piece of this, when I fill the stove full, yes, I'm experimenting.
 
this are about real time in and out
 

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I don't see any smoke? I see clouds... It's a video
 
If you wanted to do it with instrumentation and not by eye then a digital flue thermometer would be best. Depending on the stove, but mine would work best if I got the flue probe to 700F and held it there while the stove was warming up, using the air control to manipulate that temperature. Once warmed up I'd try to hold 550-700f depending on how much heat I need from the stove.
 
Cold start or reload?
it takes longer to turn down on a cold start. On a reload as soon as I have good secondary combustion I will turn its down. If it has good hot coal bed. I can usually just go down to 1/2 then final air setting. The stove top temps respond slow but once it’s back to 400F I should be at or will be at final air setting within 10 minutes.
 
If you wanted to do it with instrumentation and not by eye then a digital flue thermometer would be best. Depending on the stove, but mine would work best if I got the flue probe to 700F and held it there while the stove was warming up, using the air control to manipulate that temperature. Once warmed up I'd try to hold 550-700f depending on how much heat I need from the stove.
For sure. I've got an Auber digital with cat probe thermocouple given to me by Todd, and there's no guessing with this setup. I know exactly what's going on with the reburn with the instant feedback given by the meter.
 
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If you wanted to do it with instrumentation and not by eye then a digital flue thermometer would be best. Depending on the stove, but mine would work best if I got the flue probe to 700F and held it there while the stove was warming up, using the air control to manipulate that temperature. Once warmed up I'd try to hold 550-700f depending on how much heat I need from the stove.
yes I have a laser thermometer, where do I have the damper, right above the stove, I always read below 500 (external) but the fumes temperature will be double? Do you mean internal or external temperature?
 
yes I have a laser thermometer, where do I have the damper, right above the stove, I always read below 500 (external) but the fumes temperature will be double? Do you mean internal or external temperature?

I'm talking internal temps, measured with a probe type thermometer.
 
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Cold start or reload?
it takes longer to turn down on a cold start. On a reload as soon as I have good secondary combustion I will turn its down. If it has good hot coal bed. I can usually just go down to 1/2 then final air setting. The stove top temps respond slow but once it’s back to 400F I should be at or will be at final air setting within 10 minutes.
Both, I'm probably only now understanding that closing the air a little at a time, it is necessary to wait a little, for the entire system to settle on that setting, previously maybe I closed too much, too soon, and the fire died shortly after,
It's a longer learning curve than I thought! However if I start cold top down, It doesn't seem wrong to start reducing air right away if I see flames flapping too much.
 
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Yes, the time constant of a model describing stove operation will easily be longer than 10 minutes - so it easily takes that much time to settle in a new situation after changing something (e.g. the air).
 
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Both, I'm probably only now understanding that closing the air a little at a time, it is necessary to wait a little, for the entire system to settle on that setting, previously maybe I closed too much, too soon, and the fire died shortly after,
It's a longer learning curve than I thought! However if I start cold top down, It doesn't seem wrong to start reducing air right away if I see flames flapping too much.
A thermocouple flue probe thermometer makes all the difference if you are really trying to run as low as possible. You can see in 60 seconds that you turned it down too far.