No real secondary burns

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bigealta

Minister of Fire
May 22, 2010
768
Utah, NJ
I tend to look at this way.....
Getting to secondary combustion is a balance between heating and maintaining flue temp and keeping heat in the firebox.
To increase fire box temp as fast as possible, you have to slowly close the primary air.
Most recommend closing in 1/4 increments. Close, monitor flue temp. Repeat. Until you find the sweet spot. That is good secondary combustion, flue temp normal and stove temp at your desired output.
Some setups can close primary all the way. Some can't.
Mine cruises best at 1/8 open primary.
Most of the fun has been figuring out how to run my stove!
Well put, that’s pretty much my set up to a tee.
 

neverstop

Member
Oct 11, 2020
135
new hampshire
I'll add that there are multiple types of secondary flames. Transitioning from pre-EPA to an EPA Cat stove I initially was mistaking secondary combustion for "normal combustion". Secondary combustion can occur directly above the wood, at the secondary air ports, any place in the fire box with combustible fumes/heat/oxygen. So one split (usually in the front) may have active flames on it and the split behind it may be off gassing and producing dancing secondary flames directly above it. It's easy for me to see the difference now but initially I was oblivious.

At least with my setup I don't get the secondary flames out of the air ports unless I'm running ~575+ STT (this of course also depends on the amount of wood I load). 450-550 I usually get dancing secondaries or a small section of secondary that will expand to a larger flame and then contract and repeat. I've also noticed that usually the dancing/more lazy secondaries are usually accompanied by a small active flame on one split. Sustained secondaries from the air ports are usually not accompanied by an active flame. However, there are instances where the opposite occurs for both situations above.

Always something to learn, everytime I think I have it down I learn something new on here.
 

snobuilder

Feeling the Heat
Dec 16, 2021
432
WI
I'll add that there are multiple types of secondary flames. Transitioning from pre-EPA to an EPA Cat stove I initially was mistaking secondary combustion for "normal combustion". Secondary combustion can occur directly above the wood, at the secondary air ports, any place in the fire box with combustible fumes/heat/oxygen. So one split (usually in the front) may have active flames on it and the split behind it may be off gassing and producing dancing secondary flames directly above it. It's easy for me to see the difference now but initially I was oblivious.

At least with my setup I don't get the secondary flames out of the air ports unless I'm running ~575+ STT (this of course also depends on the amount of wood I load). 450-550 I usually get dancing secondaries or a small section of secondary that will expand to a larger flame and then contract and repeat. I've also noticed that usually the dancing/more lazy secondaries are usually accompanied by a small active flame on one split. Sustained secondaries from the air ports are usually not accompanied by an active flame. However, there are instances where the opposite occurs for both situations above.

Always something to learn, everytime I think I have it down I learn something new on here.
Totally agree the slow dancing flames that seem to flow back and forth or up and down between fuel and secondary tubes is indeed reburn of off gasses.
It doesn't have look like a gas grill effect.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,673
central pa
When I was running the regency I would get the jets of flames at the tubes for a few hours. Then dancing flames above the wood for an hour or so. It will vary allot by the stove the draft strength air settings and fuel.
 
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