Secondary Combustion

[mjrotor]

I have the same insert and that doesn't look like much secondary combustion to me, compared to what's possible. Once I've got temperatures above 400, I can pull that bottom air lever fully out then push it back in just the slightest detectable amount, maybe 1/16" and have roaring secondary flames with barely a glow from the bottom of the logs. That gives long, clean, efficient burns. I rarely need more heat than minimal cruising, but if I did, another 1/8" is plenty. "Medium" air setting (lever half way?) is what I use to get to 400, keeping it there for an hour sounds like wasted heat up the chimney to me.

It also depends on wood type, and of course, how well it's seasoned. Hickory produces the most secondaries of the wood types I've got.

TE

This is why I was posting. I feel that I should be seeing a lot more coming out of the secondary tubes. Do you put a lot of wood in your stove when the temp is at 400? Also, once you add the wood, how long do you wait before shutting the air down? I think I just have to figure out when to shut the air down. Also, I wonder if my stove is at temp too. I don't have a thermometer, so it's hard to say. I feel the second fire, the stove should be at temp.

 

[Ludlow]

They dont usually light complete like a gas stove burner. They flames flicker across and back and forth as the gasses hit it in different places.

 

[mjrotor]

I can see the burners blazing for about ten to fifteen seconds when the air is completely closed. After about 30 seconds, they will die down. Should I expect them to stay lit longer? see the below video that I did today. I can see some flames on top. Am I possibly closing the air down to early? What are the expectations for seeing the secondary tubes light up and how long typically?

 

[David.Ervin]

My Quadrafire 4300 does something similar if I get the fire blazing and then close it down. I suspect it's that the wood is still offgassing a ton when the primary air closes down, so the secondaries burn real hard until that slows down, then die back to some reasonable level as things get to a steady state. Really, if you can get to a steady state of moderate flame on the logs and secondaries together, you'll be producing a healthy amount of heat with a pretty clean exhaust. Don't worry about getting every single burner hole lit at the same time.

 

[Pertzbro]

This second video looks much better. You can tell how hot it is and how much draft you have by how aggressive those flames are.

How tall is your chimney, what is the temperature outside? What kind of wood and how long has it been cut,split,stacked? Have you tested moisture of the wood?

Wet wood will severely damper temperatures, off gassing and secondary combustion. I also believe a weak draft can do that too, but your second video shows good draft.

 

[mjrotor]

This second video looks much better. You can tell how hot it is and how much draft you have by how aggressive those flames are.

How tall is your chimney, what is the temperature outside? What kind of wood and how long has it been cut,split,stacked? Have you tested moisture of the wood?

Wet wood will severely damper temperatures, off gassing and secondary combustion. I also believe a weak draft can do that too, but your second video shows good draft.

Thanks for the input. The temp outside is mid 30's. My chimney is 30 FT, at least. The wood is below 30, but I don't think it's all under 20. The wood has been seasoned for a year. I need to get the wood more seasoned.

 

[mjrotor]

My Quadrafire 4300 does something similar if I get the fire blazing and then close it down. I suspect it's that the wood is still offgassing a ton when the primary air closes down, so the secondaries burn real hard until that slows down, then die back to some reasonable level as things get to a steady state. Really, if you can get to a steady state of moderate flame on the logs and secondaries together, you'll be producing a healthy amount of heat with a pretty clean exhaust. Don't worry about getting every single burner hole lit at the same time.

thank you for your reply

 

[mjrotor]

They dont usually light complete like a gas stove burner. They flames flicker across and back and forth as the gasses hit it in different places.

thanks for the input

 

[Pertzbro]

Get some of these. Throw in one or two on your second and subsequent reloads. it will help your stove burn better with the wet cordwood you have.

https://btpellet.com/page/pressed-fuel

You may also find something similar at some big box stores.

 

[MAD MARK]

Those flames aren't lazy at all.

Air needs turned down more, or with a 30'chimney you need to block off the secondaries inlet a little.

 

[Dobish]

The secondaries in my Oslo are never purple. You must have some magical wood there



PS

How do you like the EcoFan? I was thinking of picking up the large version.

i love my ecofan. i can definitely tell when i forgot to put it back on the stove when reloading!

 

[begreen]

I can see the burners blazing for about ten to fifteen seconds when the air is completely closed. After about 30 seconds, they will die down. Should I expect them to stay lit longer? see the below video that I did today. I can see some flames on top. Am I possibly closing the air down to early? What are the expectations for seeing the secondary tubes light up and how long typically?

That's good secondary combustion considering the wood is not fully seasoned.

 

[mjrotor]

Those flames aren't lazy at all.

Air needs turned down more, or with a 30'chimney you need to block off the secondaries inlet a little.

the last video was with the air fully closed. The flames got lazy about a minute later. The video is when I initially fully closed.

 

[deborita3]

Ya 12 hours burn times are very subjective. 8 hours is more realistic and 10 hours is achievable once you perfect burning with your stove. If you are seeing more flames above when turned down , thats a good thing you're burning clean.

8hrs of burn time? I can only get about an hour with my quad 3100i before I have to reload. I keep the air down and still can't seem to get several hours.of burning.

 

[deborita3]

Hi guys,

I am trying to learn more about the secondary combustion. Does the attached video show good secondary burn? It's set on medium air control. I am wondering if I should shut it down more. It's been like this for about an hour. I have a Lopi Freedom.

Hi.
How did you upload the video? I tried but got an error msg saying the file was too large even though the video was only a few seconds long.

 

[SculptureOfSound]

What I find weird is I can have the fire down to just secondaries (blueish orange) with a stove top of say 450...no visible smoke in the box and it seems that it is all burning, but still have smoke coming out the chimney.

It's not until I get the stove top to closer to 550 that I get only the heat ripples. Any idea why?

My guess is too much secondary air that then evacuates the smoke up the chimney before it can all burn at 450...it's not spending enough time in the firebox. At 550 the internal temp is a fair bit higher so even though the air isn't spending any more time in the firebox more volatiles are being ignited. Plausible theory?

 

[mjrotor]

Hi.
How did you upload the video? I tried but got an error msg saying the file was too large even though the video was only a few seconds long.

I put the video on Google drive and then
used the embedded link

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