What does your fire look like?

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HollyE

New Member
Jan 8, 2016
20
Ozark Mts, AR
I'm a newbie with my Buck Stove 74. Before getting it, I read as much info as possible and watched lots of "how to" videos on starting my fire and using my stove. I've only had it for 2 weeks and I feel like I've come a long way since the first day. I think one mistake I may have been making from the beginning was expecting to have a roaring fire the entire time. I would get frustrated when it wasn't and constantly poking it, tending it, etc. which was exhausting. I would wonder how in the world yall were getting wood to burn with big rolling flames for 8 hours. Now I'm wondering if that's not the case. I can keep smallish flames going, or have very red hot coal logs with blue flames skimming the top and I'm up to getting it to last 5 hours before reloading. The fire seems to go through cycles, and sometimes dying down quite a bit but then builds up, etc. So my question for you experienced burners is beyond the initial start-up, what does your fire look like? Pictures would be super helpful. I want to make sure I'm on the right path.
 
I only have roaring, rolling flames for about 3 hours, maybe 3.5. After that it's mostly a stove full of glowing orange coals for a while.
 
I'm not familiar with your stove's operation, but normally I might have as much as 2 hours of flames at reload and then 10-20 hours of glowing wood or blackness. If it's below zero outside, I have to run harder so I have flames longer.
 
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I don't have that style of stove but... after loading some damp wood I loaded up some cottonwood bark.... (3 rows of brick, about 9 inches over all high, plus or minus ashes that need to be cleaned out)
hot stove 2.jpg
 
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Hi Holly.

Yep.. Stoves burn in cycles, as you are discovering.... and the longest part of that cycle is post-flaming.

The cycle begins when you light or reload. Next stage is when the wood is flaming. Next stage is when you are able to turn down the air and then the secondary flames engage. Next stage is when the secondaries begin to die away... at this stage you might get a few stray flames or some of those blue flames you describe. Then there's the final stage of the cycle,which is red coals and no flames. This is probably the longest stage.

When I started burning in a wood stove - not that long ago - I reloaded the stove too soon during the coal stage, making my overall burn cycle sorter than it needed to be. Then I went through a stage of seeing how long I could leave the coals before I reloaded... It's surprisingly long! Then I got to my present stage, which is more about comfort than trying to achieve the longest burns I can (as if it's some kind of an Olymipic sport!).. in other words, I reload when I feel the room will soon be too chilly :)

How long the entire burn cycle lasts depends on lots of factors: stove size, what wood you're burning, how strong your draft is.. How cold it is, how cold YOU are... etc.

Most folk here have way bigger stoves than me, my typical burn cycle is just over one hour of flames and secondaries and then two hours of blue flame and coals. Then I reload.... If it's not too cold out, I'll get an extra hour at the coals stage, so around four hours in total.... So in my case 1/4 of my total burn cycle duration has visible flames.
 
I appreciate the comments, I have learned a lot on this forum and each day am getting more acquainted with my wood stove. The comments here have been extremely helpful in understanding the actual burn times and what to expect. We are getting the coldest temps yet this weekend so I feel much more ready for it.
 
You firebox is a little larger than mine but close so our experience should be similar. Like Fiona says there are stages and yours are going to be longer in duration because of the larger firebox if running a full load. My goal is to get to a clean cruising secondary burn as soon as possible. I load the stove, open the primary and leave it open until the load takes off and the firebox is full of flames. Once at that stage I try to start cutting the air back without losing the flame and look for the secondary tubes to be adding flames at the baffle. How soon you can do this depends on whether it was a hot load or cold load but the idea is the same. If you shut it down too much, you smoke out the neighbors. If you leave it open too long, you are wasting btus up the pipe.

For me, it might take 30 min on a cold/cool load to get to cruising on secondaries with primary between between 0 and 1/8th open. My manual recommends an aggressive fire a couple times a day to ill call it warming up the pipe. So on the cold loads the primary is normally open for the first cup of coffee (15 min) and then stepped down from there. After that the secondary burn (mainly a pillow of fire at the baffle and tubes) might be pretty active for 2 hours or so and then it drops to coaling. I can normally easily restart form active coals at 7-8 hours and still have a 200f stove. Some folks like to drive the stoves to a higher stove top temp with the primary air faster too.

It is funny how much weather can impact how you have to operate your stove. For me, cold dry weather increases draft which fuels the secondary tubes much better so I can shut thing down sooner and tighter.

If your wood is dry, you should not have to open the door between loads. Once the firebox is up to temp, the secondaries should keep things going. If wood is over 20%, that's a problem you will be fighting until you resolve it. There is a learning curve to these tube stoves for sure. Dry wood makes things very much better though!

Is your stove an insert or freestanding? do you have a moisture meter and a stove top thermometer?

If you can get osage orange (hedge wood) there and get it dry, you will be golden!
 
Generally, you should have flame through most stages, though the appearance will differ - and the control of flame is generally made through changing the air supply vs poking the wood. You generally only need to physically poke at the fire if a log has shifted and rests against the glass, or if you need space to add a log, or to rake out the coal bed.

In the beginning, you usually have large opaque yellow / orange flames (like a candle flame) and similar to what a typical fireplace or campfire looks like. This is a cool, relatively sooty flame. Carbon soot and various hydrocarbons are coming off the wood, but the soot is glowing - giving the yellow color. The flame isn't hot enough to burn it completely and the inside of the stove may be relatively cool, too.

As you char the outside of the wood, heat up the stove and close down the air a bit, you should start getting hotter flames. This should start to be a 'self reinforcing' cycle...hotter flames heat the firebox, firebox reflects more energy making flames hotter, etc. You need careful control of the air here...too much air and it uselessly flushes through the stove cooling things down and hurting the heat-building cycle. Too little air and the fire doesn't develop all the heat it can to build the self-reinforcing cycle to the full extent.

These will generally turn translucent blue / purple with orange or white tips. This is sort of a neutral flame... fairly hot and a combination of actual gasses coming out of the wood and some carbon still burning off the surface.

For the main portion of the burn, you'd have mainly translucent blue / purple "ghost" flames which are very translucent.

In the last stages, you may see baby blue translucent flames dancing over the coal bed. All of the large / complex hydrocarbons have burned and you're in the pure carbon cycle now...the orange glow is hot carbon reacting with the air and the blue flames are carbon monoxide being burned to carbon dioxide.


Then to top it off, it's worth noting all of this can change a bit with the type of wood being burned. Some of the softer more resinous woods, pine, fir, etc tend to exist in the 'yellow / orange' cycle a lot longer while some of the harder woods oak, hickory, hedge, etc seem to jump to the blue/purple stage quite easily. Also woods which don't leave much coal bed sometimes don't give much for the final 'carbon' stage, but those which produce great coals can give quite a show for hours...and a great bed of coals to grill on!
 
I'm not familiar with your stove's operation, but normally I might have as much as 2 hours of flames at reload and then 10-20 hours of glowing wood or blackness. If it's below zero outside, I have to run harder so I have flames longer.
This sums it up for me too. Even with dry hardwood, I never get more than 2ish hours of rolling flames. Maybe 3 if I reduce them to small flames but rarely every do. I would rather have a shorter, hotter flame output than a long, low flame output. After that several hours, you get to stare at coals for a while and the temperature of your stove will very slowly fall.
 
I now generally monitor the temp inside the rooms I'm heating and run the stove accordingly. If you can, focus on your house envelope. Once the rooms are up to 68-72 range, I keep a low level of coals, adding a split or two every now and then sustain the current temp.
 
To answer a few questions above, I'm burning oak and cherry. I don't have a moisture meter but plan on getting one. I haven't got a thermometer either because since this is an insert, I've read that the temps can vary and I wouldn't even know what temps to look for or where to put the thermometer.

When we first got the stove installed, we quickly learned that the wood we had was too green so we had a couple of ricks of dryer wood brought in. It's definitely dryer than the first batch we tried but I don't know what the moisture level is. It seems to burn well and lights fairly quickly from hot coals.
 
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