Secondary burn envy

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Dec 8, 2007
55
Chesepeake Bay
My Jotul 3 Cb has been burning fine this year with well seasoned wood. But I've yet to get a decent secondary burn of any kind. It is a rare and glorious sight, no matter how hard I try. I was left thinking a secondary burn was something you kind of chased and maybe lucked into until I visited a friend with a Jotul insert and his secondary burn was simply awesome: consistant, ethereal and efficient as can be, and it appears effortlessly, the guy's a newbie and has only had his stove a few weeks. I've been burning for years and nothing doing. My friend complains of a weak draft and mine is a pretty strong one, other than that I can't explain differences. Any theories or simple explanations? If I could get a secondary burn half as beautiful and functional as his I'd be a happy guy.
 
I've got the next size up Jotul and I typically get a good hour or two of the light show on reloads with 3-4 splits.

Tell us more about the chimney stack and where you're getting your wood.
 
I see very little of the up top light show in my F3. With the tiny firebox it is hard to leave enough combustion space above the wood for that kind of stuff.
 
It's very elusive. N/S loading and dry wood is start. Get the stove up to 500 deg at least then throw in a dry split and shut down the air. That's how mine work anyway. Most of the time this works. Mines never like the ones you see on YouTube.
 
My wood's fine as well as my draft(a strong one) and burning habits. I'm inclined to agree that perhaps the smallish size of the 3cb simply doesn't allow room for all the chemical/fire/combustive things that need to happen, happen. My friend's insert firebox is huge by comparison and, just in looking at it in action, has a lot more room to work with. My Jotul 3 takes three splits and it's full with just enough room for a healthy primary burn let alone anything else. Those same three logs in that fireplace insert barely get that stove off the ground. Love my Jotul3 but wish the salesman I had had given me half the good advice I get here.
 
Not sure why people want to buy doll house stoves. :cheese:
 
The more full my insert is and the further the air is choked the better the secondary burn. I can get solid floating secondary flames for hours on a packed full load with the air closed all the way down. If I just put in 3 or 4 splits the flames are better but its much harder to get secondaries. I fill my insert up to within a half in or inch of the burn tubes. Once its fully involved I choke it down to about half and the secondaries kick in but I still have plenty of flame on the bottom. A few minutes of that an I can choke the air all the down and it will float flames only on the top for 2-3 hours or until the wood starts to coal and collapse. Must just be different stoves and air flow characteristics.
 
Guys ya gotta realize that the F3 has around a .8 cubic foot firebox. Great little stove but the operative word here is "little".
 
Maybe it is the wood. I have a Lopi Republic 1250 with a 1.6 cf firebox and I get secondaries all the time. the secondaries look best when there is a few inches of space above the wood, but they still occur even when the wood is almost otouching the secondary burn tubes.
 
I could get a decent, but short secondary with most fires in the F3CB. There isn't enough volume for it to last more than about 15-20 minutes. The next size up Castine would get about twice that. One difference might be that I was burning mostly softwood in it, doug fir, soft maple and alder. What stove top temps are you seeing with the stove? Are they even from side to side? Another thing to check would be flue temps to see if the draft is so strong that secondary burning is happening in the flue. How tall is the stack on the stove?
 
Englishteacher said:
My wood's fine as well as my draft(a strong one) and burning habits. I'm inclined to agree that perhaps the smallish size of the 3cb simply doesn't allow room for all the chemical/fire/combustive things that need to happen, happen. My friend's insert firebox is huge by comparison and, just in looking at it in action, has a lot more room to work with. My Jotul 3 takes three splits and it's full with just enough room for a healthy primary burn let alone anything else. Those same three logs in that fireplace insert barely get that stove off the ground. Love my Jotul3 but wish the salesman I had had given me half the good advice I get here.

"My wood's fine..." I really do not like seeing this type of answer.

It seems to be the pat answer a lot of folks give but most folks find in the end that their wood is not all that great. So what is fine? What type of wood is it, when was it cut, when was it split and how was it seasoned? Those are questions that need answers before anyone can state that their wood is fine.

Please do not think I am trying to be a smart alek here because I am not. It is just that most times when someone is having a problem burning wood it is because their wood just is not as good as they think it is.
 
My wood is fine. :coolsmirk: Red and white oak. Cut, split, stacked and top covered since 2007.
 
It has taken me lots of fiddling with the stove to figure out what circumstances are ideal for long secondary combustion. other then the heat i depend on I figure this is a goal of using this type of stove, that way its burning clean. My firebox is small as well, about 1.7FT^3. I am forced to split small and place my wood rather then just throw it in. I was given a bunch of shorties from some friends awhile back. i am taking about split cut off like 4-5 inches in length, some more like 2 inches. when I would load the stove with these it was like burning coal. lots of airspace inbetween the wood and the secondary combustion went off much sooner and easier then normal splits. .8ft^3 is a real small box. try cutting a bunch of wood up into 4 inch blocks and give it a try.

oh weather depending i can get the gates of hell secondaries on some days others a bit more lazy.

Hope that helps
 
As always lots of good advice here, I'm as confident as one can reasonably be that the firewood quality is not an issue, but the idea of smaller splits for smaller stoves certainly makes sense. My draft is very strong, double-walled interior metal chimney pipe straight up 20 ft up to a cathedral ceiling. I've thought about installing a disc damper to slow things down a little and maybe let all that heat stay in the firebox longer. When the stove top temp is around 500 degrees the chimney pipe is about 220 about five feet up-- and that's double walled, sound like a proper ratio? Might a disc damper help or should we just leave well enough alone. This little Jotul heats things up pretty good once it gets cranking and all that stovepipe is putting heat into the house also albeit pretty high up there.
 
I have the 3cb too. I get secondaries on occasion but good overall cruising temp around 400-450. My wood has been c/s/s for just over 1 year
 
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