Do I have secondary when.....

Many describe what they see below the tubes like the Northern Lights.
There's some good videos of it on Youtube.

Here's a video of a Lopi Liberty achieving secondary combustion. Watch especially around the 0:50 to 1:05 mark. When you see the fire shift to the top of the wood, you're seeing the smoke burn. Makes for a beautiful fire.

http://www.youtube.com/watch?v=N-5yFVYSXhw

Would it look somewhat like this? This is my Revere cruising at 575 with a full load of wood and almost all the way closed on the damper.

Pretty good for $25. LOL !

I have a related question. I can definitely get to secondary burn, but it doesn't last. It will last for a few minutes, and tonight was the first time I saw the jets of fire shooting out of the tube in the top of my Napoleon. In fact, I don't know what the baffles are made of, but they were glowing. So, this lasts for a few minutes, and then the flames are gone and I have glowing coals. There's a good sized load of wood in there, so it's definitely not burned down to coals.

My suspicion is I'm not waiting for the stove to get hot enough before I'm closing off the air. I don't like to let it run for too long fully open, so after it's burning brightly and everything is charred, I close it back to half. Should I leave it at half until it gets to a certain temp? right now it's at about 500 * stovetop, and there are a few blue flames licking around the wood, but not what I'd call a light show.

Wood is well seasoned.

Any ideas?

I know there is a story in there somewhere. What's the deal with that 25 dollar Lopi ?

What's this obsession with secondary burn? Primary air is not a bad thing and doesn't need to be choked off to force charcoal and a secondary burn. The whole point of superheated secondary air is to extend the combustion of residual gasses that otherwise condense in the chimney and/or stink up the neighborhood with creosote.

The secondary air does not have to make it appear that the flames are coming from the tubes. That is just a stove salesman's parlour trick. Don't choke off the primary for a parlour trick. Adjust the primary to regulate the burn to meet demand along with appropriate loading.

DavidV said:

I know there is a story in there somewhere. What's the deal with that 25 dollar Lopi ?

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Here's the link to the thread I started on this stove.
https://www.hearth.com/econtent/index.php/forums/viewthread/26638/

I didn't take any before pictures, but it only took a day to get it wire wheeled and painted. Of course the paint stunk for 2 burns afterward.

LLigetfa said:

What's this obsession with secondary burn? Primary air is not a bad thing and doesn't need to be choked off to force charcoal and a secondary burn. The whole point of superheated secondary air is to extend the combustion of residual gasses that otherwise condense in the chimney and/or stink up the neighborhood with creosote.

The secondary air does not have to make it appear that the flames are coming from the tubes. That is just a stove salesman's parlour trick. Don't choke off the primary for a parlour trick. Adjust the primary to regulate the burn to meet demand along with appropriate loading.

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No obsession, just learning the stove. I'd prefer to not have the stove guttering all night, and do not feel comfortable leaving the air open while sleeping, particularly in a stove that has a reputation for "taking off". I come here to learn, and terms like "obsession" are not particularly helpful. JMO

Johnny B, what do you mean by a Napolean has a reputation for taking off? We just installed a Napolean 1400 and that "taking off" is a major worry for me. :/

beagler said:

I have very small whispy flames and my secondary tubes are not completely lit? My stove top temp is cruising at 500 deg.

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You need two things for secondary combustion, heat in the top of firebox (greater than 1100ºF), and gaseous fuel (carbon monoxide, smoke, etc). If you've got enough heat but only slow release of gaseous fuel from your wood (good seasoned hardwood) your secondary combustion will be gentle and sporadic, maybe just hovering in the upper part of the firebox, rather than an uninterrupted fierce stream of flame that appears to be pouring out of every single hole along the secondary air supply tubes.

I haven't seen it yet, but it's been mentioned more than once on here. I tend to be a bit conservative with the primary air - perhaps too conservative. Old habits die hard - My last wood burning experience was with a monster smoke demon steam boiler. If I wasn't careful with that thing, I'd have the radiators clanking up a storm and the thermometer up to 80. and it was a hungry, hungry beast.

I did check for creosote when the weather was warm a few days ago. There is a light coating of soot-like creosote, not teh dried molasses we used to get way back, more like a gritty powder. I ordered a chimney brush, and will give it a sweep when it arrives. then I'll have a better idea of how I'm doing.

Johnny B. said:

...terms like "obsession" are not particularly helpful. JMO

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Sorry, my wife calls me obsessive all the time. Maybe because I have OCD.
It might be a tad obsessive when someone videotapes it and posts it on YouTube. Maybe not.

I understand concern about a stove running away. I've had many stoves over the years some of which I would wake up to see cherry red. I don't think it's possible for it to get that bad with today's stoves.

Still, one needs to learn how to stoke it and adjust the air. If you get it too hot and choke it too much, you just make charcoal. Too cold and you just make smoke and creosote. Somewhere in between, there is a happy medium.

On my first RSF, I had to reduce the primary air because I had very good drafting. On my current RSF, I had to increase primary air to help burn down the coals because my current chimney doesn't draft as well. My first RSF had too large a notch cut out of the butterfly and I could not turn down the secondary air enough.

LLigetfa said:

What's this obsession with secondary burn? Primary air is not a bad thing and doesn't need to be choked off to force charcoal and a secondary burn. The whole point of superheated secondary air is to extend the combustion of residual gasses that otherwise condense in the chimney and/or stink up the neighborhood with creosote.

The secondary air does not have to make it appear that the flames are coming from the tubes. That is just a stove salesman's parlour trick. Don't choke off the primary for a parlour trick. Adjust the primary to regulate the burn to meet demand along with appropriate loading.

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My understanding is that too much primary air allows too much heat to escape and be wasted. Cutting back the primary air will increase the stove temps and the heat put out by the stove. I would appreciate it if some of the more experienced hands here can confirm or correct my understanding.

Ken

Ken45 said:

I would appreciate it if some of the more experienced hands here can confirm or correct my understanding.

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Would you like to quantify "more experienced"?

I had a RSF Onyx in my former home for 5 years before I sold it and built my current home 10 years ago. I liked the Onyx and so put one in my new home as well. That means I have 15 years experience with the Onyx.

That might not mean much however because the Onyx doesn't have a separate control for primary air. I did however tweak the primary air on both stoves (less on the first and more on the second) to compensate for differences in draft.

The secondary air supply is there whether or not the flames "appear" to be coming from the tubes or not. If the stove isn't hot enough, the secondary air doesn't get superheated to the point of extending the combustion. As I already mentioned, insufficient primary air can lead to too much charcoal buildup and you can end up with a huge bed of glowing coals, good for cooking a steak but probably not enough heat to keep up with demand.

But hey, every stove is different and so too are other factors such as draft, wood species, size, dryness, and stoking methods. I'm not saying I'm right and you're wrong, only to not get fixated on that secondary flaming jets look.

Ken,

Your spot on except if you cut the air down to fast or too far you can choke the fire, most stoves and users find the "sweet spot" where you know where to set it and at what temp. For my stove i get it cranking to about 450deg then close all the way, she'll heat up over 700 sometimes but usually round 650 max then settle at 600 or so and then slowly cool down to 300 and then I reload.

[quote author="Ken45" date="1226445368
My understanding is that too much primary air allows too much heat to escape and be wasted. Cutting back the primary air will increase the stove temps and the heat put out by the stove. I would appreciate it if some of the more experienced hands here can confirm or correct my understanding.

Ken[/quote]



Too much primary air will cause it to burn hotter (faster) than it should/needs to. I leave my primary open until the stove gets to the temperature I want it to run at and then I shut it all the way down (pull it all the way on my stove), and then it gets nudged back in just a smidgeon for all night, or a little bigger smidge to hold it up at the temperature I first brought it up to.

Now on the other hand, the bypass can allow too much heat to escape and be wasted.

wxman said:

Ken,

Your spot on except if you cut the air down to fast or too far you can choke the fire, most stoves and users find the "sweet spot" where you know where to set it and at what temp. For my stove i get it cranking to about 450deg then close all the way, she'll heat up over 700 sometimes but usually round 650 max then settle at 600 or so and then slowly cool down to 300 and then I reload.

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This is so true and it varies by wood species. I can cut the air all the way down with almond(similar to oak) in my stove, but usually have to leave it open just a smidge when burning pine. Just one more factor to consider.

myzamboni said:

almond(similar to oak) in my stove,

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Off topic: How long does that take to season compared to oak?

CZARCAR said:

the air from the secondaries is an airwash for the stove's heat,up the chimney.

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That's not true. The secondaries only deliver a relatively small quantity of air and once the fire reaches the coal stage the flue temperature drops, the draft drops and the secondary air almost stalls.

bokehman said:

myzamboni said:

almond(similar to oak) in my stove,

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Off topic: How long does that take to season compared to oak?

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about the same amount of time (maybe a little less)

myzamboni said:

bokehman said:

myzamboni said:

almond(similar to oak) in my stove,

Click to expand...

Off topic: How long does that take to season compared to oak?

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about the same amount of time (maybe a little less)

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I'm burning some right now. It's been split about 8 months but still doesn't seem to be in it's prime. I really need to pack it full or the secondaries go out when I reduce the air. With the two year old oak I don't have that trouble.