True North TN-25c

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EbS-P

Minister of Fire
Jan 19, 2019
5,972
SE North Carolina
Just Browsing and ran across this.

It appears to have some automated controls but can can’t figure out what it’s controlling. I will read more.

I hope This is a better catalyst implementation than Jotul did. And why release it on a True North stove and not s PE stove.

Have wood burners become to lazy to manually operate a damper. I’d like to see one in action with some data.
 
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That’s nifty! My guess is they don’t want to scar the PE name if it doesn’t work well. Passive cat technology with electric combustion assist… my WAG is they preheat the cat with electrons.
 
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We’ll, 2 thermocouples and 2 fans.

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It makes sense that they would test bed this on a single-model. It's a good way to work out issues that may show up outside of the lab testing environment. They did this with the EBT-1 and made significant changes for the EBT-2 a few years later. I was part of that feedback loop via Tom.
 
It looks like the cat is fairly small and just doing the cleanup after the secondary burn. I'd like to see an animation or video of how it works. It's good that it qualifies for the 30% tax credit and I'm glad they stayed with the N/S loading firebox. It would be fun to play with one of these stoves for a winter.
 
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I noticed that in the manual. I wonder if this is their plan to keep ahead of the next emission cut. It seems like an add on more or less.
 
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It looks like the cat is fairly small and just doing the cleanup after the secondary burn. I'd like to see an animation or video of how it works. It's good that it qualifies for the 30% tax credit and I'm glad they stayed with the N/S loading firebox. It would be fun to play with one of these stoves for a winter.
I noticed that in the manual. I wonder if this is their plan to keep ahead of the next emission cut. It seems like an add on more or less.

it’s just barely get the tax credit at HHV of 76%. So the small cat is the smallest size that gets the needed HHV emissions are improved but not as good as a BK.
 
I'm curious to see how this works, the manual doesn't provide many clues.

To me it appears that the 2 motor drivers/controllers run the cat bypass, and maybe the secondary air control? With the primary air control being manual still.
 
I'm curious to see how this works, the manual doesn't provide many clues.

To me it appears that the 2 motor drivers/controllers run the cat bypass, and maybe the secondary air control? With the primary air control being manual still.
Secondary air control based on firebox and flue temp but without primary air setting knowledge …. I want to know how that works. Temps exceed set point close air down. They definitely have not sold me on this system yet.
 
Secondary air control based on firebox and flue temp but without primary air setting knowledge …. I want to know how that works. Temps exceed set point close air down. They definitely have not sold me on this system yet.

Yeah I was thinking about that. I think it's possible, just target a certain temperature for secondary. Except I think if the temp gets too high you add more air, to ensure there is enough oxygen for complete combustion.
 
it’s just barely get the tax credit at HHV of 76%. So the small cat is the smallest size that gets the needed HHV emissions are improved but not as good as a BK.
FWIW, the Ashford/Sirocco, Chinook 30 series are also 76%. It's an arbitrary line. The difference between 76 and 78% is trivial.
 
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Secondary air control based on firebox and flue temp but without primary air setting knowledge …. I want to know how that works. Temps exceed set point close air down. They definitely have not sold me on this system yet.
It looks like it supplements control of the primary and secondary air.
 
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It looks like it supplements control of the primary and secondary air.


Jeez, I was really overthinking that. Just use the ecu to control the minimum burn rate based on firebox and cat temperature.

Cool idea though, should be able to achieve a slow low burn without the risk of smoldering.
 
Jeez, I was really overthinking that. Just use the ecu to control the minimum burn rate based on firebox and cat temperature.

Cool idea though, should be able to achieve a slow low burn without the risk of smoldering.
And/or it cuts the air at high temp’s to limit high end temps/output.