Is STT indicative of total BTU output?

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flamontagne

New Member
Dec 19, 2022
29
Québec
This is probably a silly question. Suppose I have two identical stoves side to side. One is fully loaded and the other has only 2-3 splits in it. If the STT is the same on both stoves, say 650, does it mean that they both give about the same amount of heat at this particular instant? I know the stove with the lighter load will not remain at 650 as long as the other one but is it the only difference?

I ask out of curiosity because the STT on my stove (PE Super LE) always seem to peak at 650 no matter the load size.
 
This is probably a silly question. Suppose I have two identical stoves side to side. One is fully loaded and the other has only 2-3 splits in it. If the STT is the same on both stoves, say 650, does it mean that they both give about the same amount of heat at this particular instant? I know the stove with the lighter load will not remain at 650 as long as the other one but is it the only difference?

I ask out of curiosity because the STT on my stove (PE Super LE) always seem to peak at 650 no matter the load size.
No. It's about the temperature at every place on the stove at that moment in time. Some stoves are hot all around and some are only hot on top. Think barrel stove vs. some heavily insulated double walled modern epa job.
 
It also depends if they have a fan or not
 
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This is probably a silly question. Suppose I have two identical stoves side to side. One is fully loaded and the other has only 2-3 splits in it. If the STT is the same on both stoves, say 650, does it mean that they both give about the same amount of heat at this particular instant? I know the stove with the lighter load will not remain at 650 as long as the other one but is it the only difference?

I ask out of curiosity because the STT on my stove (PE Super LE) always seem to peak at 650 no matter the load size.
If the stoves are of identical design, then yes, heat output will be similar for two stoves at the same STT.

But as @Highbeam already noted, two stoves of differing design will have different energy transfer for the same STT.

Also, don't confuse energy and power. Energy is power integrated over time, or conversely, power is energy per unit time. If they have similar efficiency at each phase of the burn, total energy will be similar, even if power is very different.
 
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If the stoves are of identical design, then yes, heat output will be similar for two stoves at the same STT.

But as @Highbeam already noted, two stoves of differing design will have different energy transfer for the same STT.

Also, don't confuse energy and power. Energy is power integrated over time, or conversely, power is energy per unit time. If they have similar efficiency at each phase of the burn, total energy will be similar, even if power is very different.
Although even with the same design the stt could be the same due to secondary combustion heating that area. But due to a smaller load of wood the rest of the stove may be a bit cooler leading to lower overall BTU output. That being said I doubt the difference would be enough to make a noticable difference
 
Although even with the same design the stt could be the same due to secondary combustion heating that area. But due to a smaller load of wood the rest of the stove may be a bit cooler leading to lower overall BTU output. That being said I doubt the difference would be enough to make a noticable difference
Yeah, we are in complete agreement there. That's why I used "similar", rather than "same". I think the mechanical conductivity of the stove materials will swamp any differences resulting from the ratio of primary to secondary burn, when staying within the same design.
 
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Yeah, we are in complete agreement there. That's why I used "similar", rather than "same". I think the mechanical conductivity of the stove materials will swamp any differences resulting from the ratio of primary to secondary burn, when staying within the same design.
I put a stove top meter on my cat stove for a couple of years. The stove top was above the 1000 degree catalyst and pretty much always the same temperature regardless of stove output.
 
Although even with the same design the stt could be the same due to secondary combustion heating that area. But due to a smaller load of wood the rest of the stove may be a bit cooler leading to lower overall BTU output. That being said I doubt the difference would be enough to make a noticable difference
That's exactly right. There are also a lot of other variables like draft strength, wood species variations, sapwood vs heartwood, and user operation. The timing of the air shutdown is also a notable factor. It also depends if the stove is stone cold or on a reload.
 
This is probably a silly question. Suppose I have two identical stoves side to side. One is fully loaded and the other has only 2-3 splits in it. If the STT is the same on both stoves, say 650, does it mean that they both give about the same amount of heat at this particular instant? I know the stove with the lighter load will not remain at 650 as long as the other one but is it the only difference?

I ask out of curiosity because the STT on my stove (PE Super LE) always seem to peak at 650 no matter the load size.
absolutely not. My stove top can read 550 and I could lay against the side without even feeling warm during a startup whereas a good # of flames are touching the top plate of the stove. At 400 I could burn my hand on the side of the stove 5 hours into a burn session.
 
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