Secondary burn questions

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colophoto

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Jan 3, 2014
56
denver
Hi everyone,
More newbie questions...I have a VC Montpelier insert and I'm trying to get a sense of operation ( this is my first ever). Watching my fire I mostly have a fire centered on the logs, early on the flame will be above the logs burning the gas. Looking on YouTube I see lots of fires up on top where the air pipes are. In a week and a half I never really see flames up there. I'm burning mostly pine. I've been paranoid about over firing and I'm not having a smoldering fire or much n the way of visible smoke out the chimney. It looks like a nice little fire but nothing like the videos, even the videos of stopped down fire.
I looked up in my liner while installing a block off plate today and it is filthy already, seems way early. So I'm wondering, might I not be burning hot enough? Should I always see some of the flames at the top? Is this something you can give ideas on without seeing?
Also, I have Amir thermometer in the mail. I read that the secondary fire needs almost 1000f to burn. Most stove temp things I see suggest 500-650. I know those are taken at different places. For an insert am I looking that high if I take the temp at the fire?

Thanks for all of the help!
 
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500f stove top will give you around the 1000f needed for the secondary's to kick in.
Once you char the load up good and get the stove top to more then 500..say 600 then you should be able to cut the air back in steps to get the light show to start.
I don't know your stove at all but the primary air may have to be almost shut all the way for that to happen.
 
So since I have an insert and it is pretty much flush with the wall, where do I measure my temp?
 
In order for the secondaries to kick in on my unit, I need well seasoned wood. I also need a hot fire at least 500*. Lastly, after a good fire is already established, I need to cut back the air to about 1/4 or less, and then the secondaries will kick in. But if I'm using questionable wood (higher than optimal moisture content), then getting secondaries is out of the question. Hope this helps.
 
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I just fooled around with my QF 4100 to see about secondary burn. I never paid much attention to it as long as it heats the house.

So this morning i start a nice stack of about 28% wood, certainly not good wood. I did get some nice secondary burn and dancing fire but only after it got super hot, lowering the fan to the minimum and closing the air. Once i put air in it it goes away or if I run the blower on high it goes away.

Give it a try.

I have a video but I can't get it to upload.
 
So many variables - stove, fuel, temp(inside stove and outside ambient) flue, chimney, etc... they all work a little differently but also ALL do the same thing. Start by making sure you have dry fuel - use bio bricks or kiln dried if you are not sure of your own and this will eliminate the biggest X factor in the equation. I can get secondaries to go at 250-300 sometimes - just depends on the fuel and how HOT the stove is. If I am loading onto a bed of coals I can cut the air back almost immediately with secondaries going - in a cold stove I may need to get it to 400 before any secondary action.

Point being, there is no one answer and you will have to play with your stove to know for sure.
 
thanks everyone. I did some experimenting today and mostly no dice, another dirty looking fire. I'm really thinking that the seasoned wood I got sold isn't so seasoned. it sure sounds right when I drop it from a short height on the patio. some go thunk, I put them back, many make a higher/louder clank/crack.
amazon says my moisture meter is lost in the storm. I guess we'll see. maybe I'll run to the grocery store and buy a bundle. the tree hugger in me doesn't love the thought of burning a dirty sooty fire all the time. neither does the guy who is going to have to clean it.
 
I am not an expert by any means but I do have the VC Montpelier and based on your post you have at least 2 fundamental problems. The first is using Pine. It might be ok for kindling but it will build up creosote. Try and go with hardwood instead. My Montpelier loves to bun well seasoned oak, cherry, and maple. The other problem is more than likely wood that has not been seasoned properly. Fully seasoned wood should feel light and almost sound hollow when clapping two splits together. A moisture meter might help to check but be sure to re-split one of your logs and measure the newly exposed wood.
With the right wood a strong and clean fire in the Montpelier is easy. If your wood is slow to light up when reloading over hot coals it is a red flag. Burning. Good wood should show zero smoke out of your chimney. With good wood your glass should be fairly clear with minimal hazing. Black glass is usually because of poorly seasoned wood.
I also use Envi blocks once I have things going as they burn nice and hot. I usually alternate cordwood and Envi's. The result is a lot of heat and a clean burn with my damper almost fully closed.
With a good burn in your Montpelier you will have little if any smoke smell in the house. It took me a month or so to really get the hand of burning but now I have a good fire going in less than 20 minutes everytime.
With the Envi Blocks I never put more than 3 or 4 in the stove as they get really hot. Start using 2 at a time until you get used to them. When putting 3 or 4 in I pack them close to limit air flow keeping the temperature under control.
My wife is super picky and at first she hated the insert until I got my technique going.
Keep looking on this site as I learned a huge amount here and it has infinitely contributed to my satisfaction with my VC Montpelier.
 
Pine creates no more creosote than any other wood if dry and burned properly.
Many out west and in Alaska and Canada only have pine or fir to burn exclusively, and no worse than others as far as creosote build up.
Time to dispel the myth.
 
Hey welcome to the forum. Sounds like the culprit is your wood. Most firewood dealers do not actually have seasoned wood.

It will help to split your wood small and bring it inside for a couple of days if you can. That will help dry things out a bit. As seabert said, a lot of guys have success burning enviblocks or other compressed wood can help when mixed with cordwood.

Here's a quick video of my insert cranking secondaries with dry wood burning cleanly.
 
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Nice secondary video with clean glass - I love the lazy flame but this sub arctic blast has not allowed for much of that here lately. I have needed the full raging crazy flames shooting out all over the place in a random controlled chaos! I am so glad we will be seeing 20's and 30's again starting today so I can go back to lazy fires. Reached 20 yesterday and my dog and I were able to get out in it and take a look at the drifts around the wood piles. Rabbits have been hanging out under there and he loves to inspect their tunnels.
 

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Thanks everyone. Played with it this am and I see a slow lazy fire with a distinct second fire up top. Can't get the fast rolling like some of you show.

I'm fully willing to believe that my wood isn't ready but my new moisture meter came and on a fresh split suspect piece I get 10.9%. I keep measuring and even pieces that make a deeper "not ready" thunk they still read well under 20%. Several make the lighter louder crack when hit together but the ends aren't discolored or cracked at all.:(
 
If it is being used correctly on a freshly exposed face of wood it may be defective. Return the meter?
What do you get for a reading if you push the probes into your palm?
 
Palm reads 31.3% pressed gently to but no stuck into skin. Piece of silver maple that sounds really dry reads 15.2%. Just found a big hunk of pine from the pile, few little cracks in the end, split it in half, reads 9.8 to 9 in various spots. The pine doesn't have a lot of end grain discoloration, the outer 2" of wood under the bark is light gray. Testing a random handful of splits most are near 10% whether they sound right or not.
 
Nice secondary video with clean glass - I love the lazy flame but this sub arctic blast has not allowed for much of that here lately. I have needed the full raging crazy flames shooting out all over the place in a random controlled chaos! I am so glad we will be seeing 20's and 30's again starting today so I can go back to lazy fires. Reached 20 yesterday and my dog and I were able to get out in it and take a look at the drifts around the wood piles. Rabbits have been hanging out under there and he loves to inspect their tunnels.
Glad to know I'm not the only one that has to have the thing really rocking and rolling to keep warm. 0-15 degree temps here lately. Not at all what we've been used to!
 
Im not sure if youve measured the wood when its outside in the cold or if its warmed inside first but you could bring some of your wood into the house and let it warm up right through and then split it and check it with the moisture meter. The meters dont work very good on very cold wood. Im not sure if it would help much though as it seems by your readings that even if warming it up a bit changed you by a few percentage points you should have good moisture content. If the pine was stored away from light exposure then it could still be dry even if the ends are white. Ive had Pine stored indoors for years with no light exposure and no discolouring or checking at the ends and it was very, very dry but this was a unique situation.
 
I suppose the pine could have been effectively out of light. we self served out of a huge huge pile. some of the top bits felt damp so I threw them aside and picked from deeper in the pile. warming the wood produces much the same results.

thanks for everyone's help and ideas!
 
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