Small fires vs. big fires

[chutes]

I must be doing something wrong. After learning from so many on this forum, I've found that my house is warmer when I do small fires, with smaller splits than when I pack the stove full (obviously, I stack if full for overnight, but this question is just about the waking hours).

I've tested this with same relative temperatures outside, and have found that if I burn a couple of splits at a time only, the heat seems to radiate better through my house. I feed it a new split every 90 minutes or so. Temp on the oven is about 450F. If I pack it full, open the air to char the wood real good, then adjust to about 1/2 open, the temp on my oven is still about 450F, but the temperature doesn't seem to radiate as well through the house. Temperatures far from the stove read about 3 or 4 degrees cooler than temps when I do just a couple splits at a time. Can someone describe what I'm seeing here, or does this not even make sense?

To be honest, since this is still new to me, I don't really mind tending it every 90 minutes or so, since "tending" it means banging the burning splits with my poker and throwing a new split on top. But, if my "style" of burning is all wrong or I'm somehow hurting my stove, I'd love to get it right.

 

[skinnykid]

kinda weird if you have the same oven temp no matter how many splits you put in and how you adjust the air. But the temps in your home are different.

 

[chutes]

exactly right. and the temp in the same room is lower as well when stove is packed full vs. small fires. with small fires, temp in the room is quickly in 80s and get warmer all night long. With packed stove temp in stove room is in high 70s even though stove temp is same. I agree that it does not make sense, but though maybe someone might describe for me why it seems to radiate better with small fires than fires with fully packed stove...

 

[skinnykid]

how long do the temps stay with the different loads?

Maybe one is hot and fast vs. less hot but more prolonged?

Just a stab in the dark.

 

[cmonSTART]

One thing to keep in mind is that theoretically, throwing a new split on every hour - while there is still active flame in the firebox - is wasting wood. So they say anyway. The idea is heat energy from the from the flames has to go into boiling out any remaining moisture and is lost. So, while the house may be warmer, supposedly you're using more wood. That's the conventional wisdom anyway.

 

[cmonSTART]

OH ya, something I've noticed with my Englander is throwing wood on like that makes the coals build up excessively.

 

[chutes]

I haven't noticed any difference in terms of coal build up, but I'll keep an eye on that.

Regarding the amount of wood, I did count splits both ways and there wasn't a significant difference, but counting splits isn't very scientific. For example, the day that I tended the fire more, the splits might have been larger on average than the day when I packed the firebox, thus meaning that I was using more wood.

But, it didn't appear that I went through any extra wood.

Doesn't seem that I'm in any way hurting my stove by doing it this way. Would you agree or not? If so, I certainly want to change, but if not, then I'm pretty content with this method during the day and packing it full for overnight.

 

[madrone]

Not an expert, but here's my theory: constant feeding means lots of shorter, closer together cycles of heat. A long, full burn means a long, slow curve to the heating cycle. Feeding = lots of temp peaks over the same period of time where a full stove = one peak. The time it takes for the heat to be lost by the house is a big part of this.

The problem, as I understand it, is that you're not maximizing the efficiency of the stove. You may not be going through a whole lot more wood, but you might be going through a little more, and you're increasing the odds that you don't get complete burning of gases. Potential increased creosote risk. Are you seeing smoke?

It makes sense to burn small, hot fires, but only if you don't reload until the coals are mostly gone. I burn this way when I'm home. It's more fun, anyway.

 

[chutes]

. Are you seeing smoke?

I see smoke only on start-up, and that's it. Other than that, there is every indication that it is burning very clean. In fact, it has been about a week of burning mostly 24/7 and I've not yet had to even wipe the glass on the door. It remains crystal clear as the day of my first break-in burn, which was weeks ago.

 

[Rockey]

The first thing I would do is make sure you are comparing apples to apples. You need to have other variables equal in both scenarios. Was ithe amount of sun out both times the same? What time of day was it? Are there fans throughout the house that may have been on? Are all the doors open or closed? If both cases are about equal then I'd start looking at things like - Was the amount of flame with the smaller splits greater or lesser? Is the secondary combustion about equal? Is the integrated temperature over time higher or lower?

 

[madrone]

. Are you seeing smoke?

I see smoke only on start-up, and that's it. Other than that, there is every indication that it is burning very clean. In fact, it has been about a week of burning mostly 24/7 and I've not yet had to even wipe the glass on the door. It remains crystal clear as the day of my first break-in burn, which was weeks ago.

I'd say you're doing fine. If you're alright running it this way, I can't think of any reason not to. When I have a full firebox, I find I spend a fair amount of time adjusting the flow anyway, so I'm inclined to burn small loads for more even heat.

 

[whrlkng]

I have sometimes noticed on a smaller burn that the top of the stove seemed to get hotter than on full loads, and a possible reason that I thought about was that, initially, the large wood load tends to block flames ( or heat from the coals? ) from hitting the top of the firebox. It could be that the overall temp of the firebox is the same, just hotter in different spots, but just an observation. I don't have a thermometer, so can't really confirm this other than the blistered-hand test, so YMMV. Mine is a sheet-metal, so I might be observing bigger swings than most people wood see. So, possibly you have more time where the firebox roof is exposed to "open-flame"? Doesn't seem like this would be dramatically different in heat out-put overall tho.

The best method for me is usually to put a medium load in, set air for average style initial burn, then as soon as possible after wood crumbles to coals close the air all the way. Depending on density of the wood, I can get about 3-9 hrs extra heat at roughly 900-1500 watt oil-heater output equivalent ( stove still too hot to lay a hand on at 6-9 hrs). The timing of the close is important, if I wait too long after the coals form it will shorten the bonus-stage considerably. Probably makes a difference in having a sheet-metal too, as a cast-iron might let most of that lower level heat go through and out. ( I haven't been able to duplicate the extra time on a VT Cast. Intrepid )

 

[chutes]

Yeah. Also, the Pacific Insert is Pacific Energy's middle of the line insert (I believe). Smaller than the Summit. So, 2-3 splits would qualify as a medium sized load. My firebox "looks" full when they're in there and not tightly packed. Now, if I take the time to tightly pack in 7 or 8 splits, I find that - even though the thermometer reads the same temp of about 450F - for some reason the heat seems to radiate throughout the house better on the 2 to 3 splits at a time vs. tightly packed.

Bear in mind that I am a true beginner as regards inside burning, so I might just be packing wrong or something. I continue to experiment, but one thing that I cannot complain about is that I have not turned on my oil heat since I started burning full time. Not once. I am anxious to see if that is true in the heart of winter, but right now it is in the 30s outside and it is 86 in my living room, 71 upstairs in my kids rooms, and 66 on the far side of the house. I can live with all these temps, and I'm writing this while wearing shorts. Hard to complain.

One other note is that I find that the 2 to 3 splits at a time produces a more traditional, "aesthetically pleasing" fire than the fully packed stove, so when I have company, I think I'll always burn this way - but, again - that could be just cause I'm packing it wrong. My primary motivation for starting this thread was to make sure that, if I want to burn 2 to 3 splits at a time, I'm not hurting my stove or contributing to creosote buildup, and thus far the responses seem to suggest that I'm not doing any harm (I think).

 

[madrone]

If your glass is clean, and no smoke, you probably need not worry. Check it in a month if you can and see if you have any buildup. Every "how to use a woodstove" website/stove manual I've ever seen recommends small hot fires over large smoldering loads.

 

[Ithaca]

chutes said:

"One other note is that I find that the 2 to 3 splits at a time produces a more traditional, “aesthetically pleasing” fire"


I think the difference is in heat radiation. With 3 splits your fire is getting plenty of O2 and you see bright white flames which radiate the most heat out of the front window.

With a packed stove, much of the fire/flame is blocked by the wood in the stove and you don't get as much radiation out the front.

I have noticed this also when I pack the stove fully. It doesn't radiate as much out the front.

 

[Todd]

I think it will get old fast burning this way and you will go through more firewood, but if it works burn it that way til the house is where you like it, then fill her up for a longer burn to maintain temp. Personally when I'm burning 24/7 I like to figure out a daily loading schedule depending on the weather and work and I could fill the stove 2,3 or even 4 times per day if I'm home all day. The less tending the better for me.

 

[Chettt]

You are probably getting more of a secondary burn with the few splits versus an over packed firebox. As to the stove temperatures being equal and the room('s) having different ones, it has to be wind, amount of sunlight, heat from dishwasher or showers etc. I'm still burning scrap wood and making lots of small hot fires. Trying to save the real wood for real winter weather.

 

[fallsfire36]

My Buck stove definitely throws a ton of heat out the front glass when burning smaller hot fires.

 

[BrotherBart]

Get that stove up to 500+ where it can maintain secondary burn on top of the wood when you ease the primary back down and loaded it will heat longer and better with a a load going through the normal burn cycle than with the split at a time method. Below 500 it is just playing steel fireplace.

 

[schortie]

Clearly I am no expert, but it seems that if you're opening and closing the door, either on top or in front, every hour or two you're releasing a lot more heat directly than you would if the stove stayed closed and merely radiated the heat. When I open the top of my stove the room temp jumps up a degree right away - more than when the stove is running closed for a period of time. But like I said, you probably don't want to listen to me, I'm a new guy.