2023/24 VC Temperature discussion thread

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My stove backpuffs every so often. Its not frequent by any means.

Backpuffing happens when there is a build up of gasses.. the wood is offgassing alot. And you get a small flairup of flame and the gasses ignite. The secondary flames you see in the box is a good combination of the air and the offgassing mixing and burning

If the stove looks like its going to back puff Ill just turn the air up slightlymaybe moving the primary air up 1/8 of an inch just enough to get a small lazy flame

Todays burn was pretty low with the primary air 2/3s back for the majority of the burn like 4 hours, when I started to get secondary burns in the firebox and it was inconsistent I just nudged the air slightly and got 1 small lazy flame and it settled back in.. This really didn't change the heat output.. after I got to alot of coals and past the offgassing I dialed the air all the way back for the long burn..

Heres a couple pictures from today

20231121_062956.jpg 20231121_063037.jpg
 
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My stove backpuffs every so often. Its not frequent by any means.

Backpuffing happens when there is a build up of gasses.. the wood is offgassing alot. And you get a small flairup of flame and the gasses ignite. The secondary flames you see in the box is a good combination of the air and the offgassing mixing and burning

If the stove looks like its going to back puff Ill just turn the air up slightlymaybe moving the primary air up 1/8 of an inch just enough to get a small lazy flame

Todays burn was pretty low with the primary air 2/3s back for the majority of the burn like 4 hours, when I started to get secondary burns in the firebox and it was inconsistent I just nudged the air slightly and got 1 small lazy flame and it settled back in.. This really didn't change the heat output.. after I got to alot of coals and past the offgassing I dialed the air all the way back for the long burn..

Heres a couple pictures from today

View attachment 319159 View attachment 319160
I wish I could keep my glass that clean! If I run hot enough to keep it clean, it would be 125 degrees in the cabin.
 
I wish I could keep my glass that clean! If I run hot enough to keep it clean, it would be 125 degrees in the cabin.

So Im not running hot all of the time. Really I burn low.. alot.. I just wait until alot of the offgassing is done and turn the stove back..

ObviouslyI get the stove up to temp, engage the cat let that get to temp, then the air gets cut back. I cut the air back 2/3s closed and let it burn SST was probably just at 500 upper 400s I let the load burn down letting it offgass then I cut the air back all the way and let it burn the rest of the day Stove was probably in the upper 300s Just as a rough guess Id say from the time I turned the air back to the time I turned the air all the way back was like 2.5 hours The box was like 2/3s full and it burned from about 6am to 3.30pm
 
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So Im not running hot all of the time. Really I burn low.. alot.. I just wait until alot of the offgassing is done and turn the stove back..

ObviouslyI get the stove up to temp, engage the cat let that get to temp, then the air gets cut back. I cut the air back 2/3s closed and let it burn SST was probably just at 500 upper 400s I let the load burn down letting it offgass then I cut the air back all the way and let it burn the rest of the day Stove was probably in the upper 300s Just as a rough guess Id say from the time I turned the air back to the time I turned the air all the way back was like 2.5 hours The box was like 2/3s full and it burned from about 6am to 3.30pm
Ahhh that's interesting, something I did not pick up on before. You wait a couple hours before dialing the air down....
Is that your normal low burn procedure?

I thought you got the cat hot and then stepped the air down to 0 more quickly.
At 2.5 hours in you are past the backpuffing stage.... I suppose that's the point.

Also interesting your STT was at 500 with 2/3 air closed (33% open).... seems higher than my stove.

More tweaks for me to try.
 
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Ahhh that's interesting, something I did not pick up on before. You wait a couple hours before dialing the air down....
Is that your normal low burn procedure?

I thought you got the cat hot and then stepped the air down to 0 more quickly.
At 2.5 hours in you are past the backpuffing stage.... I suppose that's the point.

Also interesting your STT was at 500 with 2/3 air.... seems higher than my stove.

More tweaks for me to try.
After my consistent burns for the past couple weeks, the only challenge I need to solve is the glass. I get everything up to temp and then drop the air to 50% and let it run, that is my standard run right now. That consistently leaves me with black glass. I know at 10% or 0 I'm going to get the black but I would have figured running at 50% I could mostly avoid that, obviously not. Maybe I'll start running the air at 75% for a couple hours once I get everything up to temp and then drop it down for the rest of the burn.

500 at 2/3 air would be high for my stove as well. I would fall closer to 450, maybe 475 at that air setting.
 
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Ahhh that's interesting, something I did not pick up on before. You wait a couple hours before dialing the air down....
Is that your normal low burn procedure?

I thought you got the cat hot and then stepped the air down to 0 more quickly.
At 2.5 hours in you are past the backpuffing stage.... I suppose that's the point.

Also interesting your STT was at 500 with 2/3 air.... seems higher than my stove.

More tweaks for me to try.

So I burn various ways depending on what I want to accomplish.. Overnight burns as described before.. load.. let the cat get to 1k.. dial air to 0

As in how Iv burned the past couple weeks..and above.. I may have made it confusing.. the air was 1/3rd open for clarification.. 2/3s closed.. To keep the glass clean many times Ill dial the air back to 1/2 or 1/3 depending on heat needs let it burn for a few hours, then dial the air all the way back. The key is to get past most of the offgassing. thats what keeps the glass clean.

In the dead of winter I dont do this because the heat demand is higher.. but shoulder season like right now I burn this way. I do it so Im not relighting the stove all the time

So for yesterday I burned most of the day on the morning's wood.. roughly 3pm there were plenty of coals left and plenty of draft to light the stove off again without having to babysit and do a cold start procedure.
I really do try to prolong my burns this time of year.. constant cold starting sucks.

Winter.. its jut reload.. burn for 8/10 hours reload again for day's at a time.. let the stove burn down.. clean.. relight.. I may shut the stove down once every 10 days or so.
 
So I burn various ways depending on what I want to accomplish.. Overnight burns as described before.. load.. let the cat get to 1k.. dial air to 0

As in how Iv burned the past couple weeks..and above.. I may have made it confusing.. the air was 1/3rd open for clarification.. 2/3s closed.. To keep the glass clean many times Ill dial the air back to 1/2 or 1/3 depending on heat needs let it burn for a few hours, then dial the air all the way back. The key is to get past most of the offgassing. thats what keeps the glass clean.

In the dead of winter I dont do this because the heat demand is higher.. but shoulder season like right now I burn this way. I do it so Im not relighting the stove all the time

So for yesterday I burned most of the day on the morning's wood.. roughly 3pm there were plenty of coals left and plenty of draft to light the stove off again without having to babysit and do a cold start procedure.
I really do try to prolong my burns this time of year.. constant cold starting sucks.

Winter.. its jut reload.. burn for 8/10 hours reload again for day's at a time.. let the stove burn down.. clean.. relight.. I may shut the stove down once every 10 days or so.
So you're keeping your glass relatively clean with the air 1/2 open to 1/3 open? Just to be very specific, you're class will stay relatively clean with air 2/3's closed?
 
After my consistent burns for the past couple weeks, the only challenge I need to solve is the glass. I get everything up to temp and then drop the air to 50% and let it run, that is my standard run right now. That consistently leaves me with black glass. I know at 10% or 0 I'm going to get the black but I would have figured running at 50% I could mostly avoid that, obviously not. Maybe I'll start running the air at 75% for a couple hours once I get everything up to temp and then drop it down for the rest of the burn.

500 at 2/3 air would be high for my stove as well. I would fall closer to 450, maybe 475 at that air setting.
I added to the confusion.... I was thinking 2/3 closed (33% open) but I did not write that..... doh! I edited my post to clear that up....

So..... at 33% air open 500 STT would be high for my stove....

Overnight burns as described before.. load.. let the cat get to 1k.. dial air to 0
Yeah that does not seem to work for me....runaway cat temps or backpuffing will ensue.... most of the time.

I am going to try 50% air at Cat=1000, then wait a few hours, then dial air back to zero. See if that works...
 
So you're keeping your glass relatively clean with the air 1/2 open to 1/3 open? Just to be very specific, you're class will stay relatively clean with air 2/3's closed?
I know your not asking me but.....

I generally do not have an issue with blackened glass at air settings above 50%. It is not perfectly clean, I do get some buildup on the lower, hinge side corners, maybe a 3"W x 5"H patch that never seems to burn off....

If I go to low air settings <30% it will go full black.... sometimes pretty heavy. But it will mostly burn off with a hot bed of coals.
 
I know your not asking me but.....

I generally do not have an issue with blackened glass at air settings above 50%. It is not perfectly clean, I do get some buildup on the lower, hinge side corners, maybe a 3"W x 5"H patch that never seems to burn off....

If I go to low air settings <30% it will go full black.... sometimes pretty heavy. But it will mostly burn off with a hot bed of coals.
I plan to play with some higher air settings to see how it responds.
 
So you're keeping your glass relatively clean with the air 1/2 open to 1/3 open? Just to be very specific, you're class will stay relatively clean with air 2/3's closed?

My glass is completely clean at 1/2 air and a little less then half way for sure.. verry close to the 1/3 open..

Ill post a picture of my stove and what it looks like when I get home in a little bit
I added to the confusion.... I was thinking 2/3 closed (33% open) but I did not write that..... doh! I edited my post to clear that up....

So..... at 33% air open 500 STT would be high for my stove....


Yeah that does not seem to work for me....runaway cat temps or backpuffing will ensue.... most of the time.

I am going to try 50% air at Cat=1000, then wait a few hours, then dial air back to zero. See if that works...

I may be a littl off on the exact STT. sometimes I have the IRgun on it before the temperature actually settles in for that air setting.. Im thinking back to yesterday and I might have shot it just to confirm that my stoves not to hot.

If you want me to I can.do a thread on this kind of a burn.. Ill post pictures of temperatures and settings
 
So this is what my stove looks like when I got home today

The air was left exactly half way damper was closed.

This was how it was set up today.. Todays high temperature was going to be like 57 degrees and the house was warm from the burn from yesterday so I did not burn overnight.

At 5am I lit the stove and got it up to temperature. did my normal cold startup. stovepipe temperature got where it need to be closed the damper let it run for a little bit.. loaded wood. I loaded to maybe 2 inches below the anirons.. so probably 25% of the box was full closed the bypass and set the air to half way. I wnt to work. this was how the stove looks now

air was exactly half.. obviously nothings in the box now because that much wood cant burn this long

there is also a picture of the current temperature in the living room

20231122_142220.jpg 20231122_142345.jpg 20231122_153922.jpg
 
Well dang
Hearing the Stt you guys are seeing with different primary air settings while in bypass and cat engaged is shocking. The only way I can get stove top temps over 450 is if my bypass is open and I'm running more air than 50% open or
I have a warm stove at 400 degrees and fill it up with a bunch of small pine or fir splits engage cat and run the primary at 100 open.
All my other wood species won't super heat the stove over 450 while in bypass on any air setting.
 
The season’s first fire was started this evening. New for this year, I added three feet of chimney. Until now there was just 9-10 feet of a straight shot and I never felt things were quite what I expected. So far this seems like a good move. The air control actually demonstrates some influence on the burn. Right now, four hours into the burn with three-year seasoned red oak and air shut down, I’ve got a stovetop temp of 602 and a catalyst temp of 889.
IMG_1185.jpeg
 
The season’s first fire was started this evening. New for this year, I added three feet of chimney. Until now there was just 9-10 feet of a straight shot and I never felt things were quite what I expected. So far this seems like a good move. The air control actually demonstrates some influence on the burn. Right now, four hours into the burn with three-year seasoned red oak and air shut down, I’ve got a stovetop temp of 602 and a catalyst temp of 889. View attachment 319284

look at the little intrepid go.. how long have you had it
 
Well dang
Hearing the Stt you guys are seeing with different primary air settings while in bypass and cat engaged is shocking. The only way I can get stove top temps over 450 is if my bypass is open and I'm running more air than 50% open or
I have a warm stove at 400 degrees and fill it up with a bunch of small pine or fir splits engage cat and run the primary at 100 open.
All my other wood species won't super heat the stove over 450 while in bypass on any air setting.

Have you checked your primary air.. or checked for an air leak around the refractory.. how old is the stove

If you dont know how to look for a secondary air leak.. let me know Ill walk you through it
 
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Have you checked your primary air.. or checked for an air leak around the refractory.. how old is the stove

If you dont know how to look for a secondary air leak.. let me know Ill walk you through it
How do you check for a secondary air leak around the refractory? Curious in CT.... hahaha

Happy Thanksgiving to you all
 
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look at the little intrepid go.. how long have you had it
We had it installed in March of ‘20 to replace a zero-clearance fireplace. The house is small and it’s pretty well insulated and air-sealed. It works out that I could put a return grill in the corner of the living room at the ceiling and blow the heat to the basement. That made a tremendous difference in our home comfort. Now it seems like I might have this all dialed in.
 
How do you check for a secondary air leak around the refractory? Curious in CT.... hahaha

Happy Thanksgiving to you all

ok.. don't laugh.. When I did the rebuild to my stove, this was a concern about not having the refractory sealed up..

What I did to make sure that I had all the gaskets compressed was, I took my smallest shop vac and put the hose on the exit side. My son placed the hose up near the secondary air intake and blew into it. Not super forcefully as to displace or tear the gaskets. I put some ash in the stove and if the ash moved I knew I had to tighten things up.. I did locate a small leak on the LHS of the refractory and adjusted things prior to finishing the rebuild..

This does work.. Its also a good and easy way to test the gaskets down the road in a few years
 
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Well dang
Hearing the Stt you guys are seeing with different primary air settings while in bypass and cat engaged is shocking. The only way I can get stove top temps over 450 is if my bypass is open and I'm running more air than 50% open or
I have a warm stove at 400 degrees and fill it up with a bunch of small pine or fir splits engage cat and run the primary at 100 open.
All my other wood species won't super heat the stove over 450 while in bypass on any air setting.
Warm here today so going to let it go out. But I put 3 big splits on at 6 this morning. Cat is at 960 now and STT at 500. Air 90% closed
 
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ok.. don't laugh.. When I did the rebuild to my stove, this was a concern about not having the refractory sealed up..

What I did to make sure that I had all the gaskets compressed was, I took my smallest shop vac and put the hose on the exit side. My son placed the hose up near the secondary air intake and blew into it. Not super forcefully as to displace or tear the gaskets. I put some ash in the stove and if the ash moved I knew I had to tighten things up.. I did locate a small leak on the LHS of the refractory and adjusted things prior to finishing the rebuild..

This does work.. Its also a good and easy way to test the gaskets down the road in a few years
Not laughing.... very clever idea. I like it.
 
Warm here today so going to let it go out. But I put 3 big splits on at 6 this morning. Cat is at 960 now and STT at 500. Air 90% closed
As a follow up my glass will darken at 90% closed. I suspect everyone's will. Typically late afternoon and early morning I run the stove wide open to get it nice and warm and take the chill out of the house and that cleans my glass. 50% air or above its always clear glass. 90% closed overnight gets me about 10 hours of burn and my house stays above 66/67. I'm fine 65 and up. Some people in the house like ~70 better. Same people wanted 61 when we were buying oil every 5 weeks so 🤷
 
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As a follow up my glass will darken at 90% closed. I suspect everyone's will. Typically late afternoon and early morning I run the stove wide open to get it nice and warm and take the chill out of the house and that cleans my glass. 50% air or above its always clear glass. 90% closed overnight gets me about 10 hours of burn and my house stays above 66/67. I'm fine 65 and up. Some people in the house like ~70 better. Same people wanted 61 when we were buying oil every 5 weeks so 🤷

buying oil sucks.. Im with you.. house was 62 at night and 68 at best during the day.. now its let the house drop to 66 and when the stoves on keep it in the lower 70s
 
Thanks woodsplitter I'll check for this tomorrow am.
As for house temps in this 70s era cabin,
I like to slowly run the place up to about 75 degrees at night and around 11pm I'll pack the stove full,
Set primary air to 5 clicks in from open, cat engaged.
This will give me about 6-8hrs of a nice slooow burn glow. The place will drop in temp to about 62 degrees by 7am.
Of course the glass is now black from that burn but I have a nice layer about 1inch deep of starter coals and the stove will still be warm. Not hot, but warm enough it's not a cold start.
I'm happy so far. Just monkeying with things to see if anything can get a little better.
 
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