Can someone explain why burning in cycles is better than adding a split every hour. Is it more efficient? Adding a split every hour keeps the stove hot.
Why burn in cycles?
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Adding a split or two every few hours is burning in cycles, just a different cycle. This is typically how we burn in milder weather. It's not quite as efficient or clean burning if the firebox is not hot enough to support secondary combustion, so we try to be sure not to let the stove cool down too much in between. We reload with a couple splits so that a hotter coal bed is maintained and the new fire is a bit more robust. The mass of the T6 absorbs this pretty well so we see little room temp variation.
When it is very cold out, good sized loads are the way to go. It means less frequent filling, more complete combustion, and enough btus to keep the house warm.
When it is very cold out, good sized loads are the way to go. It means less frequent filling, more complete combustion, and enough btus to keep the house warm.
I am not an expert but a newbie, but this website might help woodheat.org. It explains how to burn efficiently. There are three stages to burning wood. Burning off the moisture, burning off the smoke into flame then the charcoal phase where all the vapors are burned off. By adding a log every hour, you are disturbing the cycle and losing heat by opening the door and polluting your house with small particulate matter. I know it may not make sense but I think of it as respecting the fire and letting it do it's thing. I am tempted many times to throw just a log or two in but I generally load it to the gills and let it burn..........
I think it depends on the stove. In my stove, adding a log to the fire every hour or two works great. I'll open door, pack two more splits into a roaring fire and close the door before I burn all the hair off my arm. I don't need to open the draft at all. The secondaries put on a dazzling show. In my insert, adding two logs without opening the draft way up puts the secondaries out and I get a lot of smoke up coming out of the chimney. I need to let a bunch of heat up the chimney and babysit the stove for 15 minutes before I can shut down the intake again. I'm better off burning the insert in 4-6 hour cycles.
Unfortunately I have to go with the information I find here and elsewhere online because I did not grow up burning and I don't have anyone here to teach me hands on so I want to get the facts straight. I wish I had some of you here to teach me hands on but I don't. I even went to the local fireplace gallery, to see the wood stoves in action and one of the employees said I can come to see the owner fill the big mother they have there. (He only fills it I think once a day or so). She said its amazing how much he fills it and his technique. I am going to see that in person so maybe I can learn more.
rdust said:
Well, yeah... some heat.
Some of us recently discussed a study that compared efficiencies between a typical airtight stove and the identical stove operated with the doors open. There was about a 48% overall efficiency with the doors open, and a 63% overall efficiency with the stove burned as an airtight. So, yes, if you are burning it 24/7 with the doors open, you will have a huge 15% loss in usable heat, but we're talking about opening up the stove, slipping a chunk of wood in and then closing it again. A minute, maybe (if you're slow), and at a time late enough in the burn (I'll assume) that the secondaries have stopped and the stove temp has dropped a bit anyway.
A few BTUs lost for the gain of increasing the stove temp a few hundred degrees for an extra hour or two? I'll live with that trade off. You have to open it up eventually, why wait until it's no longer putting out useful heat? In the dead of winter, I need all of heat all of the time. I've tried long burn cycles. They don't work for me when steady heat output is the goal, and steady heat output is really the best way to achieve maximum heating efficiency.
GAMMA RAY said:
Well, just goes to show that you shouldn't believe everything you read... unless, of course, I wrote it. %-P
BeGreen hit the nail on the head (as usual). It's all cycles, unless you're standing there stick-feeding it all day. You do have to make sure you don't overdo it. Also, as others mentioned, it depends on the stove. With my stove, the wood added on top sends its smoke downward through the coals, and then into the secondary combustion chamber. It helps to keep the "hopper" loaded a bit. I see no disadvantage at all to adding a split every hour, but you can build up a humongous bed of red hot coals that way, and not good heat output in spite of all the fuel in there. You really have to experiment, that's the only way to optimize your stove for your own needs. Don't be afraid to try new things. Don't just do it the way we say, because it may only work well for the one giving you the advice at the time.
BeGreen said:
My wager is that a lined firebox will behave better with small loads than an unlined. Less loss of heat from combustion area. Mine works fine on adding single sticks to existing fire.
Also, to not have unburnt bits hiding under ash-bed, at least let each batch burn down to coals. DAMHIKT.
I think the cycles use less wood for the same amount of heat, the wife burns what ever way she wants too and uses way more wood than I ever do.
ToddH said:
I sometimes just add a split every hour or so . . . when we have a warm day or shoulder season day . . . more or less just keeping the fire going with a bit of heat . . . not sure how inefficient this is . . . providing I bring things up to temp and then turn down the air . . . of course just sticking a piece in the firebox and leaving the air control all the way up would eat up a lot of wood quickly . . . biggest pain in doing what you describe is being "chained" to the stove vs. just loading it up, getting the stove settled and then letting it cruise for several hours without tending to it.
With a catalytic, I think it makes sense because of the inefficiency of the loading process. First, of course, you have to disengage the catalytic airflow so it doesn't smoke. Then, most people (I think, I know I do) will burn the thing for 5min or so after they reload and before re-engaging the cat; this is in case there is some extra moisture or crap on the wood that it'd be nice to not have go through the cat. So that's a bit of time burning inefficiently.
I burn in cycles because I live in cycles. I don't need my air temps to be at 70 degrees when I'm asleep, or when I'm away at work, but I like the rooms to not get down to that refrigerator-chill feel before I build up the next fire. I'm trying to do this with the maximum amount of useful, comfortable heat while making my wood supply last out the winter. Think overlapping sine waves, where I never have to get to the bottom of the heat trough (if that image helps). The room temp is coming up on the next fire before it's had a chance to really cool off, but the wood has burned through efficiently before the next fire has started.
When I get it right, I can build fires that last all night, and hold all day when I'm away at work, and luxuriate in front of a warm fire in the evenings that I've rebuilt from a bed of coals. When I get off that cycle, I find myself awake at four a.m. in the morning rebuilding a fire, or coming home to a cool house, or noticing that the temps in the hearth room have climbed to 78F.
The stove manufacturer recommends a hot burn for about 20 minutes at least once a day to prevent creosote buildup. I try to do that at least a couple of times a day, because I don't want to go up on the roof at this time of the year, and I don't want to pay someone else to go up there to clean out my pipe. In order to do that effectively, I burn in a cycle.
I usually do that run-up fire at the point where I have a good-sized load of coals that I'm trying to burn down--just add some small hot spits, open the dampers, and let it rip. If, OTOH, I do that at the start of a cycle, with a full load, all the wood engages early, the room gets hotter than it needs to, and my wood burns up too quickly. (This is what I did when I was first learning to use this stove in this house, which came from trying to do it `by the book'. What I'd been told was to fill it up, and let it burn down. It took awhile for me to notice that a modest fire kept the house uniformly warm, whereas an overbuilt fire got the hearthroom really warm and then burned down before the upstairs rooms had gotten comfortable. I haven't quite figured out the why of that yet, but that was the point where I started thinking for myself and realized I could `learn' my stove and get better results.)
By letting it have that runup *before* I add my overnight load, or my going-off-to-work load, loading it on top of a modest bed of coals that can be capped with one split and surrounded by others that only start to burn when the cap split has burned off, the wood burns through in turns, like dominoes falling in slow motion, and my house is warm and I still have coals for the next fire when I awaken/return from work.
I get maximum useful heat from minimum wood use. My plumbing does not freeze, and we are comfortable. I'm keeping a 2000sf house warm in the middle of Alaska with no backup heat with a parlor stove and a limited supply of who-knows-how-old firewood that was cut and stacked in various locations by the previous owner, and a few racks of standing dead stuff that was cut this fall, while holding down a job, so I don't have a lot of latitude for error. At this point, I believe I'm going to make it, weather permitting; we've got a little cold snap going here that's increased my wood use. Other people in more forgiving climates and circumstances are going to have more wriggle room, and will do this differently. Your milage *will* vary, as it should. HTH.
When I get it right, I can build fires that last all night, and hold all day when I'm away at work, and luxuriate in front of a warm fire in the evenings that I've rebuilt from a bed of coals. When I get off that cycle, I find myself awake at four a.m. in the morning rebuilding a fire, or coming home to a cool house, or noticing that the temps in the hearth room have climbed to 78F.
The stove manufacturer recommends a hot burn for about 20 minutes at least once a day to prevent creosote buildup. I try to do that at least a couple of times a day, because I don't want to go up on the roof at this time of the year, and I don't want to pay someone else to go up there to clean out my pipe. In order to do that effectively, I burn in a cycle.
I usually do that run-up fire at the point where I have a good-sized load of coals that I'm trying to burn down--just add some small hot spits, open the dampers, and let it rip. If, OTOH, I do that at the start of a cycle, with a full load, all the wood engages early, the room gets hotter than it needs to, and my wood burns up too quickly. (This is what I did when I was first learning to use this stove in this house, which came from trying to do it `by the book'. What I'd been told was to fill it up, and let it burn down. It took awhile for me to notice that a modest fire kept the house uniformly warm, whereas an overbuilt fire got the hearthroom really warm and then burned down before the upstairs rooms had gotten comfortable. I haven't quite figured out the why of that yet, but that was the point where I started thinking for myself and realized I could `learn' my stove and get better results.)
By letting it have that runup *before* I add my overnight load, or my going-off-to-work load, loading it on top of a modest bed of coals that can be capped with one split and surrounded by others that only start to burn when the cap split has burned off, the wood burns through in turns, like dominoes falling in slow motion, and my house is warm and I still have coals for the next fire when I awaken/return from work.
I get maximum useful heat from minimum wood use. My plumbing does not freeze, and we are comfortable. I'm keeping a 2000sf house warm in the middle of Alaska with no backup heat with a parlor stove and a limited supply of who-knows-how-old firewood that was cut and stacked in various locations by the previous owner, and a few racks of standing dead stuff that was cut this fall, while holding down a job, so I don't have a lot of latitude for error. At this point, I believe I'm going to make it, weather permitting; we've got a little cold snap going here that's increased my wood use. Other people in more forgiving climates and circumstances are going to have more wriggle room, and will do this differently. Your milage *will* vary, as it should. HTH.
I find that adding a split or two at a time requires me to leave the primary air open more. Less efficient than a full load running mostly secondary air. I run this way at times when it's warmer out, and just figure I'll be sacrificing a little burn time for a cleaner flue.
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