What exactly is secondary burn in an insert?

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Ram 1500 with an axe...

Minister of Fire
Mar 26, 2013
2,327
New Jersey
Hi all, and what are the tubes at the top with the holes in them actually doing? Can you give details...
Thanks
 
supply super heated ( when correctly configured) combustion air to mix with volatile gases rising off burning wood, pyrotecnics at the top of fire box are the result. Less emmisions up flue means less creosote. This also improves the over all efficiency of the unit. Progress Hy-bred has both secondary burn tubes as well as catalytic combuster so that is just about as far as the envelope can be pushed with out getting insane like our automotive devices.
 
Here is a link to a short video I shot just for giggles..

In the video, the load is fully involved and charred, I am moving the primary air control lever to full closed. At the end the incoming air is being routed through the secondary burn tubes at the top of the stove, where it mixes with the fire and byproducts coming off the wood load. This secondary action increases both the efficiency of the stove at making heat, but also "reburns" almost every bit of the remaining wood gasses and particles that would otherwise head up the flue.

 
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And the link is at?
 
supply super heated ( when correctly configured) combustion air to mix with volatile gases rising off burning wood, pyrotecnics at the top of fire box are the result. Less emmisions up flue means less creosote. This also improves the over all efficiency of the unit. Progress Hy-bred has both secondary burn tubes as well as catalytic combuster so that is just about as far as the envelope can be pushed with out getting insane like our automotive devices.
Wow thank you guys, I am now feeling that I am under firing my insert, once going, I put two skinnier splits on bottom straight in, then one regular or much bigger split crosswise so u can now see a nice flame in the glass. Today I put 3 regular splits on top of the 2 skinnier ones, after a few minutes I played with the air intake, upon closing fully I started noticing flames coming from a few holes (4 pipes tota) scattered through the holes, no flames coming from front 2 pipes. Doing this for the first time I started hearing a few noises in the insert, I'm thinking normal noises because I'm running her hot. But how hot is too hot? Like I said, I put in 2 small splits to lay a pad for the 3 I put in on top for the first time. Thanks for all input. And u guys seem very knowledgea .
 
If ya got a guage on the stove try not to go over 800::F ya need to start closing down the primary air when ya git to the 400-500 ::F marks little bit at a time. do not know your stove but mine will cruise at the 600-700::F for awhile with just the secondaries dancing
 
If ya got a guage on the stove try not to go over 800::F ya need to start closing down the primary air when ya git to the 400-500 ::F marks little bit at a time. do not know your stove but mine will cruise at the 600-700::F for awhile with just the secondaries dancing
Only place to put it is on the glass. The glass area is bigger then the box. How hot can glass get before something bad happens? Thanks
 
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Your stove will melt before the ceramic glass will.
 
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Well running Mozilla Firefox and a no show will have to open up IE..LOL
 
Well running Mozilla Firefox and a no show will have to open up IE..LOL

Interesting, I can see it with my phone, and I use Firefox exclusively on the PC...
 
If ya got a guage on the stove try not to go over 800::F ya need to start closing down the primary air when ya git to the 400-500 ::F marks little bit at a time. do not know your stove but mine will cruise at the 600-700::F for awhile with just the secondaries dancing

In my somewhat humble opinion if you are at 800 stove top you have wildly exceeded the chimney safe temps at least with DuraVent plus. It is rated at 1000F continuous and 1 hour at 1400F that puts you in the 1 hour lifetime. the next step left is the one or two time over fire for minutes before the chimney is junk. If you are using skin temps as gospel I have some very bad news they are out to lunch by a lot. Skin temps and internal ones have no direct correlation in any way as there are way too many variables involved right down to paint type. The IR gun is no better as you are still not measuring what is actually going on. I have seen 700 flue gas with probe and a 400F stove on a small flare up. I am thinking all these 'rules of thumb' are all fantasy and wishful thinking at best.
Dave
 
Thanks
 
Well running Mozilla Firefox and a no show will have to open up IE..LOL

I think it may be related to FF disabling Java because of that security problem. I couldn't view embedded videos until I upgraded Java.

TE
 
I don't think 3 splits will get you near an over fire condition. 3 splits in my 30 (small / medium splits as you say) will only last an hour or so and I can leave the air Wide open with just 3 splits and not come close to 800*.

How long has your wood actually been split? Not cut.. Split and stacked? And what species is it?

Wet wood is a good indicator of no secondaries. Also, low firebox temps and to much primary air.

More wood, hotter box, and close air more (assuming wood has been seasoned at least 1 yr/split).
 
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Hi Ram Montpelier was designed for max glass view, so no good spot for thermometer... some people put it on the door frame corners, but doesn't give a good indication, at 200 degrees on the thermometer, the fire is going good at that point. So with the Montpelier, visual is best. Good active flame, with good wood, about 1/3 to 1/2 air shutter open will give good results. I know the firebox is tapered, ideally 16-18 in back with 20 in pieces towards the front. For max burn time, more wood in firebox gives more, cleaner heat out. Oh yeah, if blower isn't coming on within 45min to 1 hr, clear ashes off front ceramic area. If your blower is wired for automatic (it should be) the snap disc is up front and center underneath. Hope this helps.
 
Hi Ram Montpelier was designed for max glass view, so no good spot for thermometer... some people put it on the door frame corners, but doesn't give a good indication, at 200 degrees on the thermometer, the fire is going good at that point. So with the Montpelier, visual is best. Good active flame, with good wood, about 1/3 to 1/2 air shutter open will give good results. I know the firebox is tapered, ideally 16-18 in back with 20 in pieces towards the front. For max burn time, more wood in firebox gives more, cleaner heat out. Oh yeah, if blower isn't coming on within 45min to 1 hr, clear ashes off front ceramic area. If your blower is wired for automatic (it should be) the snap disc is up front and center underneath. Hope this helps.
Great, thank you, I have been babying it, 2 small splits and then a good split on top at a time. I loaded it on Wednesday and I'm seeing better results, clean glass, red coals 24 hr later, warmer room. I have a drafty old house and no cut off plate like people are saying u need, so I keep experimenting, I only burn dry wood but I think I'm always under firing . How much wood is proper but not too much, thank you
 
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Hi ram I like to run as much wood at a time as possible a full load. However, you know your stove best- if you can run full loads and the wood isn't super dry, prob no problem. If you got good control of airflow, no prob usually. I load up for max burn, my wood never seems too dry, but I've heard from other folks on here sometimes you can overfire a stove with a full load experimenting is always your best plan and see what works. Good luck.
 
Hi all, and what are the tubes at the top with the holes in them actually doing? Can you give details...
Thanks
Good question
When I read about these tubes, cats, thermometers, correct temps, primary air, secondary air, (probably left out a few other things) I wonder what all this stuff is. I have a 1980's era Johnson Energy Wood Burner. Actually a big red box measuring 32" deep, 24" wide, and 40" tall.
With my stove, I start fire, throw in a couple of splits every hour or so and that's it. No monitoring temps or anything else.
Ram - a little comment about your Ram 1500. I have a Ram 1500 too, but its a Ram 1500 Van. Amost every time I have to buy parts (not very often) the parts guy gives me parts for a Pick-up and not a van. And I specify Van when ordering. I did the rear brakes last summer and they gave me shoes and other parts for a pick-up. It took a couple trips back to store to straighten it out. Sometimes they'll confuse it with a Caravan too.
I think maybe I'll carry a picture of it in my wallet and show them when buying parts.
 
I load up for max burn, my wood never seems too dry, but I've heard from other folks on here sometimes you can overfire a stove with a full load experimenting is always your best plan and see what works. Good luck.

A full load of small dry stuff, such as pallet wood, is a recipe for overfire. Similar with a big load of random shorts and uglies, where they can't be packed in well, and space exists for the air to really get whirling around in the stove. If packing a stove full of medium to large splits of cord wood, you shouldn't have any trouble maintaining control, assuming your stove is in good working order.
 
How much wood is proper but not too much, thank you

There is really not a "too much".. the stove is designed to be loaded full. You CAN do a poor job of loading it, leaving too much surface area and getting a "full load" that can be hard to control.. don't stuff it full of shorts and uglies, or small splits. The load in the video I posted was 6 splits if I .rem correctly.

With the Mansfield, a 3.2 cuft box, when I reload, The size splits I am putting in are such that 6-7 fills the firebox...
 
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