Increasing Wood Burn Times

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cbscout

Member
Aug 16, 2018
93
Mid-Michigan
Hi, I've been burning in my new PE Alderlea T5 Classic insert for about a month now. It's a 2.2 cu. foot firebox. I am supposed to get pretty good burn times, manufacturer specs up to 8 hours, although I know that's not realistic, install company said expect 6 hours. However, I'm getting 4 to 5 hours(max), and its 5 hours to embers during the day (I don't burn all night). I burn about 14 to 15 hours a day on average, using ash this year (measures between 16 and 20% moisture on the fresh split). This month I went through more wood than I thought, so I just wanted to ask around and see how I could increase my understanding and hone my skills a little to help increase efficiency.

Thanks!
 
Bigger splits always help, how big are your splits now?
 
Not as big as I'd like them to be. I have another four face cord coming that are larger splits. I wanted to have full quarter splits or larger, but not all of them were. I didn't have a lot of choices this late in the season. By the end of the month I'll have hit almost 1.5 facecord.
 
Burn times are somewhat subjective. What I mean is that you aren't going to literally see flames for 8 hours. I also burn in a T5 and can get 8-10 hr burns fairly easily, sometimes even 12. This requires packing the stove full with a nice BTU wood (lately for me it's a mix of honey locust and maple), let it get cruising along and gradually cut the air down until it's all the way down. When I wake up in the morning, my silly Ecofan is still spinning which immediately tells me the stove is still hot. Basically if that fan is moving then I can almost always restart a quick fire because there's still hot coals in there. That to me equates to burn time.

If the fan is not moving by the morning, there's usually not enough in there to restart quick and easily. Usually this is when a firestarter or newspaper is needed with some small splits or kindling.
 
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Burn times are somewhat subjective. What I mean is that you aren't going to literally see flames for 8 hours. I also burn in a T5 and can get 8-10 hr burns fairly easily, sometimes even 12. This requires packing the stove full with a nice BTU wood (lately for me it's a mix of honey locust and maple), let it get cruising along and gradually cut the air down until it's all the way down. When I wake up in the morning, my silly Ecofan is still spinning which immediately tells me the stove is still hot. Basically if that fan is moving then I can almost always restart a quick fire because there's still hot coals in there. That to me equates to burn time.

If the fan is not moving by the morning, there's usually not enough in there to restart quick and easily. Usually this is when a firestarter or newspaper is needed with some small splits or kindling.
Burn times are somewhat subjective. What I mean is that you aren't going to literally see flames for 8 hours. I also burn in a T5 and can get 8-10 hr burns fairly easily, sometimes even 12. This requires packing the stove full with a nice BTU wood (lately for me it's a mix of honey locust and maple), let it get cruising along and gradually cut the air down until it's all the way down. When I wake up in the morning, my silly Ecofan is still spinning which immediately tells me the stove is still hot. Basically if that fan is moving then I can almost always restart a quick fire because there's still hot coals in there. That to me equates to burn time.

If the fan is not moving by the morning, there's usually not enough in there to restart quick and easily. Usually this is when a firestarter or newspaper is needed with some small splits or kindling.
I appreciate the response. Are you using the T5 insert, or the T5 stove? I try to pack it as full as possible. I am using ash (18-20% moisture), like I said, but am even now trying to find someone who has oak for next year. If I had the property I would buy, cut, split and season my own. I try not to cut it back too soon so it gets hot enough first, and also keeps the glass clear. See a couple spots on the glass that repeatedly develop no matter what I do.

This stove insert will crank it out enough to bring some heat all the way to the other end of my 1200 sq ft ranch, which is surprising because of layout.
Love that so I don't have to turn on the furnace. But I digress...

So even if I am seeing embers at 7 hours, and its putting off some heat, it's considered burn time?
 
I have the free standing model, and if you have embers after 7 hours and it's putting off heat or at least keeping the stovetop at or over 200 degrees (I guess I should say stove top on my free standing) I would consider it burn time. If you can rake coals, reload and somewhat quickly get it going without firestarters, kindling, etc then I would say it's within it's "burn time"...Again I think it's kinda subjective.
 
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I have the free standing model, and if you have embers after 7 hours and it's putting off heat or at least keeping the stovetop at or over 200 degrees (I guess I should say stove top on my free standing) I would consider it burn time. If you can rake coals, reload and somewhat quickly get it going without firestarters, kindling, etc then I would say it's within it's "burn time"...Again I think it's kinda subjective.
Ok, got it. It's a little harder to get accurate temps on an insert, I would imagine. But like you say, it's subjective. I know that when the embers are still red hot the stove is still giving significant heat. I guess for me when the fan starts pushing air that is not really hot enough to be warming the room well any longer, I would consider that the end of the burn time. I'll start watching it from that standpoint and see what I come up with for times.
 
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5-6 hrs on a load of ash that has a split size of 16" x 4" diameter seems pretty right, Ash is a good wood but it will burn down pretty fast, the nice thing about ash is that it does burn pretty complete, leaving lots of room during reloads.
Sometimes the visual reference of what a true cord looks like seems outrageous, 4ftx4ftx8ft, (that's a lot of wood) but the reality is that its not uncommon to go through 5-6 of those during a burning season when in the north.
This is where the "fine" tuning comes in, learning basic fire behavior in your stove, everyone has a different draft, setup, wood supply, you need to play around with your to find the sweet spots (and there different with each type of weather condition)
Others will say this is where having a block off plate for an insert with insulation on top helps extend burn times because the insert can stay warmer on a lower air setting so the result would be a longer burn time while keeping a clean burn.
Burn times for me is usable heat, not flames, not coals, just usable heat.
 
5-6 hrs on a load of ash that has a split size of 16" x 4" diameter seems pretty right, Ash is a good wood but it will burn down pretty fast, the nice thing about ash is that it does burn pretty complete, leaving lots of room during reloads.
Sometimes the visual reference of what a true cord looks like seems outrageous, 4ftx4ftx8ft, (that's a lot of wood) but the reality is that its not uncommon to go through 5-6 of those during a burning season when in the north.
This is where the "fine" tuning comes in, learning basic fire behavior in your stove, everyone has a different draft, setup, wood supply, you need to play around with your to find the sweet spots (and there different with each type of weather condition)
Others will say this is where having a block off plate for an insert with insulation on top helps extend burn times because the insert can stay warmer on a lower air setting so the result would be a longer burn time while keeping a clean burn.
Burn times for me is usable heat, not flames, not coals, just usable heat.
Yes, when I figured I was going to hit 1.5 face cord by the end of one month (even though we did get kind of a cold november) I was pretty surprised and am putting another call in to get a couple extra to make sure I don't run out. I am going to make sure I have enough available to me as it seems between december and march I could easily go through another 8 face cord.

I do, according to the installers, have a block off plate as I asked about that before the install was done.
 
cbscout, yes it's still considered burn time. Hard lesson learned from first stove I had. This was advised from the dealer. I didn't consider coal at the end of the burn cycle usable heat. But the industry does. Kevin
 
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The best marketing ploy is hearthstone that says "burntime" and "heatlife". It's a crock. At least your installer was realistic.

I will also echo that there is a very high chance that any wood you buy now will not be dry. And yes, big splits help, but need additional drying time.

Lastly, when you have wet wood, you need to give it air to make it burn. When you do that you cannot operate a modern stove correctly and maximize heat and burn times.

I went from a noncat hearthstone to a cat bk and am much happier with the length of burn and its evenness of heat.
 
The best marketing ploy is hearthstone that says "burntime" and "heatlife". It's a crock. At least your installer was realistic.

I will also echo that there is a very high chance that any wood you buy now will not be dry. And yes, big splits help, but need additional drying time.

Lastly, when you have wet wood, you need to give it air to make it burn. When you do that you cannot operate a modern stove correctly and maximize heat and burn times.

I went from a noncat hearthstone to a cat bk and am much happier with the length of burn and its evenness of heat.
Thank you. Yeah, our installer was great. When we went to them, I started with questions and they were willing to take the time. When it came to stuff like insulation around the liner and block plates, etc. they were already doing it. I had other places that were practically discouraging me from doing insulation. At any rate, they were on the ball. It does seem that the manufacturers throw those terms around quite a bit. :) I know it caused us to consider options with that spec in mind when we looked everything up. We still came up with a great insert, thankfully. The wood we have has been dry and burning great, and we've gotten great heat out of it. I was thankful to find a seller that still had wood in late fall. It was a little expensive, but he delivered it AND stacked with me.