Secondary's,only one is working.

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Depends on how hot the firebox is and the intensity of off-gassing from the wood. If the air for the secondary manifold is fed from the rear the back tube may fire first. Is this with a full or partial load of wood in the stove?
 
Depends on how hot the firebox is and the intensity of off-gassing from the wood. If the air for the secondary manifold is fed from the rear the back tube may fire first. Is this with a full or partial load of wood in the stove?
Let's start with this question ,
When should the secondary's kick in ? After a full load became a bed of coals ? Please tell me ?
 
I never have secondaries for the last 1/3 of a burn when it is mostly coal.
Mostly just the front two tubes and nothing spectacular.

Stove is a n/s casket shaped firebox though.
 
Let's start with this question ,
When should the secondary's kick in ? After a full load became a bed of coals ? Please tell me ?

Once your firebox is hot enough and you turn down the primary air. Provided the wood is dry and you have sufficient draft, of course. However, you don't need to see little "gasburners". Floating flames in the top of the firebox is also ok.
 
Let's start with this question ,
When should the secondary's kick in ? After a full load became a bed of coals ? Please tell me ?
On a cold day, with good kindling and properly seasoned wood, you should be able to have secondaries burning within 15-20 minutes of lighting a cold stove, and lasting for 2-4 hours.

Look around here there are many tips on getting a proper fire, but the most important one is dry wood.

TE
 
The term secondary may be misleading. In an EPA stove running optimally, "secondary" combustion may be the primary source of heat.

TE
 
Time to say it for the first time this season: If I have a stove full of "secondaries", I screwed up. If you have a five or six hundred stove top temp and no smoke coming out of the chimney, rest. Ya dun good.

Gas jets blowing out of the secondary combustion tubes are a parlor trick.
 
I don't even look! I get the stove at 500 or higher, and shut it down. It does it's thing!
 
As long as there is little to no smoke out of the stack, I don't worry about the secondaries.
 
Time to say it for the first time this season: If I have a stove full of "secondaries", I screwed up. If you have a five or six hundred stove top temp and no smoke coming out of the chimney, rest. Ya dun good.

Gas jets blowing out of the secondary combustion tubes are a parlor trick.
I think I know what you are trying to say, but it could be misunderstood as saying that getting secondary flames is a bad thing. For me the only time I'd look for a full compliment of jets at the tubes would be coming into a cold house on single digit days, at any other time, I want some lazy dancing flames above the logs, usually as little as possible in order to maintain a steady heat for as long as possible.

TE
 
I want as little as possible. I leave the space the stove maker intended between the load and the baffle and the burn takes place there. Not up at the baffle. This stuffing it to roof and setting off the gas show up top torching the top of the load is just wasting btus up the stack.

Burned both ways a bunch of times to find out. And the burn times and temps are the same. The difference is wood consumption.
 
I want as little as possible. I leave the space the stove maker intended between the load and the baffle and the burn takes place there. Not up at the baffle. This stuffing it to roof and setting off the gas show up top torching the top of the load is just wasting btus up the stack.

Burned both ways a bunch of times to find out. And the burn times and temps are the same. The difference is wood consumption.

Hi Brother Bart... Ok so you've baited me with what you've said here. :) If I'm recalling correctly, you used to have the same stove as me? So what's the 'space the stove maker internded' for a Jotul F3 CB?

I confess I have been loading her up to the top, leaving just enough space for the secondaries to flame from both sets of holes, thinking this was the right thing to do. Sorry if you have to do this every year - but it's new teaching for me - can you elaborate ?

With gratitude.. To you all I love to learn all this stuff!
 
I agree and disagree with BrotherBart. 2ndary burns (how/when) seem to vary greatly due to stove/insert design and even more so based on wood species and moisture content. My I3100 insert can have 2ndary tubes going with 1/2 load or full load of wood depending on species & moisture - after the box reaches a certain temp. Off gassing seems to be variable also based on fuel size - at least in my unit. What I want to see is just like BroBart said .... small dancing flames just above the wood for maximum Btu retention inside the box vs out the stack. In my unit, temp will rise with 2ndary burns; probably because I do not typically maintain a 550-600 degree temp on the face of the insert.

Visitors that haven't seen these types of stoves/inserts love to see the dragon appear though and yes, it's impressive; but for heating value I want a good bed of coals with large splits and slow dancing flames.
 
I the stove is up to temp, and there is only heat coming out the chimney, but no secondary flames, I wouldn't worry, secondary's I thought were just to reburn the unburnt smoke? right
 
secondary's I thought were just to reburn the unburnt smoke? right

That's a huge "JUST"; a large proportion of the potential heat from wood can be lost in unburned smoke, and the invisible unburned gases.

TE
 
I the stove is up to temp, and there is only heat coming out the chimney, but no secondary flames, I wouldn't worry, secondary's I thought were just to reburn the unburnt smoke? right
Not every insert & stove can have a temperature gauge ! Sometimes on these stoves there's no room for it. So then it makes it a guessing game
 
There can be good secondary burning without a light show. If the box is above 1100F, the secondaries will be burning (regardless of stovetop temp). But if the fuel is burning with a lot of active flame, you may never actually see it. If the smoke from the chimney is gone, secondaries are working. The light show will be more obvious when the primary air gets turned down and there is enough off gassing. And it can be very pretty under the right conditions. It just doesn't usually last too long. And once the fuel is burned down to coals, there won't be enough combustion products left to burn.
 
So then it makes it a guessing game
No guessing needed if its daylight, if you can see any smoke from the chimney, you are not up to temperature. I'd love to do a double camera time-lapse of my temperature and chimney smoke sometime. The sharp drop-off in smoke somewhere between 380F and 420F is dramatic.


TE
 
The sharp drop-off in smoke somewhere between 380F and 420F is dramatic.
Yeah. Although the stove top temp at which this happens will vary a lot (mine will do it at less than 200), it can be like turning off a switch sometimes.
 
Secondaries in my stove usually kick in starting at the back. Few occasions when all tubes were firey waterfalls were usually those times I happened to let 'er rip a bit too far - great show but not something I'm shooting for. Lazy flames + no smoke out the stack = no worries.
 
I would be challenged to not have secondaries lighting off with a good load of wood. I can sometimes slow them down, but not eliminate them. The wood is outgassing too rapidly to do that. They are not the goal but an outcome of rapid heating up and outgassing of the fuel charge.
 
Sometimes it happens.

secondary burn.jpg
 
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