What am I doing wrong? (thick logs don't keep the fire)

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I guess I'm confused at what model this is. The Lopi Large Flush Hybrid had a cat years ago, at least a decade ago IIRC. Is this the Declaration insert?
As far as I know, they had the Hybrid with a cat some time ago, then at some point they removed it, bringing the newer non-cat version, which I have. In this post I showed the differences between them according to their manuals. Year of manufacture of my stove is 2022. Now they don't manufacture those anymore, having a new Hybrid. A fireplace shop had few of them on a discount, so I took it. I didn't get the EPA credit, but I think my model should fit me better.
 
Yeah, good suggestion, thanks! I got that same idea yesterday when looked through my wood-related photos, where I used klin-dried wood for an outside fire for kebabs... Would be interesting to try it out in the stove with similar outside temp conditions! I will post here when I try, thanks!

Good to know, thank you! I like clean glass, but a thought that I'd have to clean it every day was a bit disappointing... Will try to leave it next time.


I think it would be more preferable method for me too, because I'm worried about the tubes at the top. Cold top-down start made them a tiny bit glowing and I think it's not very good for them.


Thank you! It helps a lot to input and support from you guys!


Makes sense, thanks. Since you mentioned that, do you have your secondary tubes always working, especially during overnight burns? I have a feeling that they work similar to a cat, in a way that secondary burn happens only above certain temperature of the stove...
On a hot reload, such as loading for an overnight burn, the secondaries will be strong at first, then gradually reduce until the coaling stage. The secondaries might last a couple hours or so, give or take. I wouldn’t worry about your burn tubes getting too hot, they are designed to withstand an extremely hot firebox. I have a short clip of nice secondaries from last winter, I will see if I can post.
 
I only recall cat versions of the NexGen Large Hybrid but maybe I missed one? Check the manual.
 
I only recall cat versions of the NexGen Large Hybrid but maybe I missed one? Check the manual.
[Hearth.com] What am I doing wrong? (thick logs don't keep the fire)
[Hearth.com] What am I doing wrong? (thick logs don't keep the fire)
[Hearth.com] What am I doing wrong? (thick logs don't keep the fire)
 
Thanks for being patient. I recalled there being this model out for a year or so but wasn't sure which size insert. Then it disappeared with the 2020 EPA requirements. Lopi doesn't have the manual up, not even under discontinued models, so I couldn't verify.
 
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As far as I know, they had the Hybrid with a cat some time ago, then at some point they removed it, bringing the newer non-cat version, which I have. In this post I showed the differences between them according to their manuals. Year of manufacture of my stove is 2022. Now they don't manufacture those anymore, having a new Hybrid. A fireplace shop had few of them on a discount, so I took it. I didn't get the EPA credit, but I think my model should fit me better.
You mean IRS tax credit, correct? EPA does not have any "credits".

BKVP
 
So I bought some kiln dried wood, that showed 7% on the moisture meter and tried to burn it with the similar outside temperature like in the first post. I must say it's night and day comparing to my "seasoned" wood in terms of burning. Only after 5 minutes I was able to close air intake completely and it still burned like my wood would have burned on 75% opened air intake. I even thought the air control broke or something :) I made a timelapse of first few hours:
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And in the morning there were some glowing coals left:
[Hearth.com] What am I doing wrong? (thick logs don't keep the fire)


Although, despite it was a very dry wood, my glass was awful in the morning... I don't know what caused that - I thought it only happens because of wood which is not dry enough... Apparently it can happen with ideal wood too. Do you guys know how to avoid it?
[Hearth.com] What am I doing wrong? (thick logs don't keep the fire)
[Hearth.com] What am I doing wrong? (thick logs don't keep the fire)
 
More than likely the fuel was too dry for your installation. Try it again, blend with fuel that is 18-24% moisture content.

Stoves are "tuned" to burn within that MC range.

BKVP
 
More than likely the fuel was too dry for your installation. Try it again, blend with fuel that is 18-24% moisture content.

Stoves are "tuned" to burn within that MC range.

BKVP
So you can burn a full load of +20% wood in a BK? Just curious because the general consensus on this site is that the wood needs to be super dry in these new stoves.
 
Blending 7% (if indeed it's that...) with 18-24% is not a full load of 20+ imo.

My experience is that below 17% or better is a world apart from anything above 18%.

To the OP: windows get black when one has insufficient air *for the moisture content of the wood*.
You say kiln-dried 7%. Was that measured *after you resplit* a piece and then measured on the inside? I personally doubt the wood was 7% on the inside if it was firewood (and not lumber).

I can get my window black in my BK with 13% wood. Just shut the air down too much. Now my stove will allow that because the cat will clean up the smoke that the smoldering fuel creates before it reaches the flue. Other stoves may have (EPA) minimum air settings that are higher than the low smolder of my stove.
But that does not mean that one can't set the air too low, because what is too low depends on what the fuel needs to burn well, and that depends on the moisture content.
 
Blending 7% (if indeed it's that...) with 18-24% is not a full load of 20+ imo.

My experience is that below 17% or better is a world apart from anything above 18%.

To the OP: windows get black when one has insufficient air *for the moisture content of the wood*.
You say kiln-dried 7%. Was that measured *after you resplit* a piece and then measured on the inside? I personally doubt the wood was 7% on the inside if it was firewood (and not lumber).

I can get my window black in my BK with 13% wood. Just shut the air down too much. Now my stove will allow that because the cat will clean up the smoke that the smoldering fuel creates before it reaches the flue. Other stoves may have (EPA) minimum air settings that are higher than the low smolder of my stove.
But that does not mean that one can't set the air too low, because what is too low depends on what the fuel needs to burn well, and that depends on the moisture content.
That's what I was curious if BKVP meant or not when he said the stoves are tuned to burn between 18-24%.
 
So you can burn a full load of +20% wood in a BK? Just curious because the general consensus on this site is that the wood needs to be super dry in these new stoves.
Not true...PFS test labs in Clackamas Oregon did an extensive test recently for Climate Change Canada. I posted a link to that study months ago.

They tested technology, fuel type but most importantly, they were looking at VOC's.

Part of the study was to find the relationship between moisture content and PM and VOC's. The PE32 had no change in PM or VOC's running up to 35% m.c.

Now this is vital. I don't think posters here say the fuel has to be "super dry", rather properly seasoned. Candidly, for the sake of burning wood here and elsewhere, everyone in every stove needs to burn properly seasoned fuel. Cleaner air, better rep for wood burners!

There is also user satisfaction that needs to be met. As posted previously, all mfgs tune wood stoves to burn m.c. fuel REQUIRED by the EPA test method. That range is 18-24%. The PM and efficiency numbers on EPA's website reflect results of heater tested to the method.

Members here know I burned NIELS exclusively for a few seasons. They performed very well. The smokey glass, rather than creosote deposits, is my experience burning NIELS, which are 7% m.c.

Burn well seasoned fuel everyone....non wood burners are voters!

BKVP
 
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Not true...PFS test labs in Clackamas Oregon did an extensive test recently for Climate Change Canada. I posted a link to that study months ago.

They tested technology, fuel type but most importantly, they were looking at VOC's.

Part of the study was to find the relationship between moisture content and PM and VOC's. The PE32 had no change in PM or VOC's running up to 35% m.c.

Now this is vital. I don't think posters here say the fuel has to be "super dry", rather properly seasoned. Candidly, for the sake of burning wood here and elsewhere, everyone in every stove needs to burn properly seasoned fuel. Cleaner air, better rep for wood burners!

There is also user satisfaction that needs to be met. As posted previously, all mfgs tune wood stoves to burn m.c. fuel REQUIRED by the EPA test method. That range is 18-24%. The PM and efficiency numbers on EPA's website reflect results of heater tested to the method.

Members here know I burned NIELS exclusively for a few seasons. They performed very well. The smokey glass, rather than creosote deposits, is my experience burning NIELS, which are 7% m.c.

Burn well seasoned fuel everyone....non wood burners are voters!

BKVP
Thank you for clarifying!
 
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Not true...PFS test labs in Clackamas Oregon did an extensive test recently for Climate Change Canada. I posted a link to that study months ago.

They tested technology, fuel type but most importantly, they were looking at VOC's.

Part of the study was to find the relationship between moisture content and PM and VOC's. The PE32 had no change in PM or VOC's running up to 35% m.c.

Now this is vital. I don't think posters here say the fuel has to be "super dry", rather properly seasoned. Candidly, for the sake of burning wood here and elsewhere, everyone in every stove needs to burn properly seasoned fuel. Cleaner air, better rep for wood burners!

There is also user satisfaction that needs to be met. As posted previously, all mfgs tune wood stoves to burn m.c. fuel REQUIRED by the EPA test method. That range is 18-24%. The PM and efficiency numbers on EPA's website reflect results of heater tested to the method.

Members here know I burned NIELS exclusively for a few seasons. They performed very well. The smokey glass, rather than creosote deposits, is my experience burning NIELS, which are 7% m.c.

Burn well seasoned fuel everyone....non wood burners are voters!

BKVP
But what was the difference in heat output?
Which is arguably the most important factor for those heating their homes with wood.
At 35% moisture my jotul non cat f400 would not even hold a flame.
 
But what was the difference in heat output?
Which is arguably the most important factor for those heating their homes with wood.
At 35% moisture my jotul non cat f400 would not even hold a flame.
Agreed! That is why I stated "User Satisfaction" as a component.

Any wood heater burning wet wood is not producing the possible heat output of that stove. They are also likely building creosote in the stove and chimney. We all know what happens next.

BKVP
 
I dont have glass on my stove. Just more to worry about and clean. It looks nice, but a PITA to keep looking good. Just my 2 cents.
 
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You say kiln-dried 7%. Was that measured *after you resplit* a piece and then measured on the inside? I personally doubt the wood was 7% on the inside if it was firewood (and not lumber).
Yeah, I did not resplit, since I thought kiln dried would be all like that. But I measured in multiple places, like on the side and in the middle - it was 7% all around. I will resplit it next time, coz I'm curious now.

I can get my window black in my BK with 13% wood. Just shut the air down too much.
But if your goal is to set it overnight, that's what you want to do, right? If you don't care about the glass - would you still burn like this next time or there is another advantage of leaving a bit more air besides cleaner glass in this case?

But that does not mean that one can't set the air too low, because what is too low depends on what the fuel needs to burn well, and that depends on the moisture content.
Well, for that kiln dried wood it indeed burned very well on the lowest: moisture content was low and BTUs were pretty high. From this point of view air was not too low. But does it mean I have to adjust the air intake not only based on that, but also on the viewing glass condition? So if I see that it starts getting dark, it means I have to add a bit more air? I'm trying to learn...

More than likely the fuel was too dry for your installation. Try it again, blend with fuel that is 18-24% moisture content.
I don't think posters here say the fuel has to be "super dry", rather properly seasoned.
That's interesting and something new for me. But it kind of makes sense, because I had a feeling (and you can see it on the video) that for a fully closed air the fire is too intense still (IMO). So maybe it indeed was kind of out of range... I thought the less is MC, the better, but it looks like I have to be somewhere in 14-16% range then with my stove for the best results?
 
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I would not say that looks like it's overly intense for a closed draft setting with 7% moisture wood. I would guess 14%-20% would all be burning well in your set up.

Fully closed drafts are not like the old stoves that actually fully closed the inlet air.
The newer stoves / inserts don't fully shut down the inlet air even when the lever is in the closed position.
 
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I dont have glass on my stove. Just more to worry about and clean. It looks nice, but a PITA to keep looking good. Just my 2 cents.
We only have solid doors for King an Princess models, but we see quite a few.

BKVP
 
I would not say that looks like it's overly intense for a closed draft setting with 7% moisture wood. I would guess 14%-20% would all be burning well in your set up.

Fully closed drafts are not like the old stoves that actually fully closed the inlet air.
The newer stoves / inserts don't fully shut down the inlet air even when the lever is in the closed position.
CORRECT!
 
But if your goal is to set it overnight, that's what you want to do, right?
My stove always burns overnight - and day. I just set it at the setting that gives me the heat output I need, and reload when it's needed. Generally that's between 12 and 30 hours depending on the weather (5 F - 40 F)

If you don't care about the glass - would you still burn like this next time or there is another advantage of leaving a bit more air besides cleaner glass in this case?
I don't care about the glass; I have the stove for heat. If it gets black, so be it. My cat keeps my chimney clean.
I am concerned that with a tube stove the glass being this dark, the chimney will see more crud than in my cat stove with a dark glass. (Modern tube stoves are fantastic clean burners, but they generally do that with cleaner glass. So the dirty glass here suggests there may be more dirt in the pipe too, given that it's unlikely that smoke would hit the windot and then cycle back to the secondary tubes to be combusted...?)
Well, for that kiln dried wood it indeed burned very well on the lowest: moisture content was low and BTUs were pretty high. From this point of view air was not too low. But does it mean I have to adjust the air intake not only based on that, but also on the viewing glass condition? So if I see that it starts getting dark, it means I have to add a bit more air? I'm trying to learn...
The glass is less of an issue, but as noted above it could be an indication of what the chimney sees too (for a tube stove). That is something you should pay attention too. NExt time do the same you did now - during the day, and look at what comes out of the chimney.
 
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I dont have glass on my stove. Just more to worry about and clean. It looks nice, but a PITA to keep looking good. Just my 2 cents.
It's more of a slow burning cat problem and it depends on the stove and how it's run. Our glass is slightly hazy after 15 yrs of service, but still stays clear. It gets cleaned it a few times during the heating season but that's it.