2023/24 VC Temperature discussion thread

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My glass is brown currently. Not burning hot enough to keep it clean.

Half load tonight when cat was at 750. Little hotter than when I'd put a full load, but I'm going to bed. 1350 cat sitting now.
 
Continuing on the topic of temperature, I want to install a stove pipe thermometer. I have a double wall stove pipe. I'm assuming I buy another Auber, but what size thermocouple is best and how have people installed them? I did do a search for this but didn't find specifically what I'm looking for.
 
Continuing on the topic of temperature, I want to install a stove pipe thermometer. I have a double wall stove pipe. I'm assuming I buy another Auber, but what size thermocouple is best and how have people installed them? I did do a search for this but didn't find specifically what I'm looking for.

I just have a regular magnetic thermometer on the oval adapter.. as high as it will go.. right where it meats my double wall pipe..

Im not super crazy with flue temps.. the catalyst does a really good job keeping things clean.. stovepipe wise.. I use the magnetic thermometer just to gauge my draft to see if I have enough to kick off the catalyst.. or if im doing a reload can I just close the damper or do I need to heat things back up.

I normally do a mid-season cleaning and run the sooteater down the pipe in January to see how the stove is running.

I was burning low alot last year.. stovepipe looked really good..

most people who dont have stoves with catalyst will need to monitor the stovepipe temperatures more and keep higher temps. I personally dont feel we fit into this category if your burning with the cat in and have the digital probe saying.. its burning at 1200 degrees.. by the time the the catalyst is done with it there's nothing left to create creosote in the stovepipe
 
Continuing on the topic of temperature, I want to install a stove pipe thermometer. I have a double wall stove pipe. I'm assuming I buy another Auber, but what size thermocouple is best and how have people installed them? I did do a search for this but didn't find specifically what I'm looking for.
As I’m sure you’re aware, magnetic sensors won’t do much for double wall pipe. I use the Condar flue guard which is specifically designed for double wall pipe. Since I’m more of an “evening warrior” than a continuous stove user, flue temps are really helpful for my repeated cold starts. Another Auber would be great if it meets your aesthetic goals. :) I know @arnermd runs a flue probe on his defiant - he might be able to weigh in.
 
My suggestion would be to buy a thermocouple reader and a type K probe. I use a reader / data logger by perfect prime TC0520, been happy with it.
 
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Dead cat?
  • Metal cat I installed in Feb, 5 2022. Maybe 3 cords on it, sat in the stove all summer. Mechanically it appears to be in good shape, some shifting of the grid but no holes, frame is in real good shape, no warping.
  • Started with 2-3 splits to get things going from dead cold, 50% air setting.
  • Griddle was up to 500, engaged cat, put air to 100%
  • Cut air back to 75% when griddle got to 600, cat temps dropped a lot
  • Reloaded on a nice bed of coals, rake to back, air to 100%
  • Throttle air back to reduce heat output, went to bed.
Glass is clean, draft is probably on the low side (not very cold last night), burned down to ash in the morning. Solid 12 hour burn.

Maybe cut air back to early?
Need to check MC.
1698667887312.png
 
Dead cat?
  • Metal cat I installed in Feb, 5 2022. Maybe 3 cords on it, sat in the stove all summer. Mechanically it appears to be in good shape, some shifting of the grid but no holes, frame is in real good shape, no warping.
  • Started with 2-3 splits to get things going from dead cold, 50% air setting.
  • Griddle was up to 500, engaged cat, put air to 100%
  • Cut air back to 75% when griddle got to 600, cat temps dropped a lot
  • Reloaded on a nice bed of coals, rake to back, air to 100%
  • Throttle air back to reduce heat output, went to bed.
Glass is clean, draft is probably on the low side (not very cold last night), burned down to ash in the morning. Solid 12 hour burn.

Maybe cut air back to early?
Need to check MC.
View attachment 317704
Doesn't seem like the cat ever lit off. I'd try it again tonight. Never used a metal cat but seems quick to be dead. Maybe just not enough coals?
 
Dead cat?
  • Metal cat I installed in Feb, 5 2022. Maybe 3 cords on it, sat in the stove all summer. Mechanically it appears to be in good shape, some shifting of the grid but no holes, frame is in real good shape, no warping.
  • Started with 2-3 splits to get things going from dead cold, 50% air setting.
  • Griddle was up to 500, engaged cat, put air to 100%
  • Cut air back to 75% when griddle got to 600, cat temps dropped a lot
  • Reloaded on a nice bed of coals, rake to back, air to 100%
  • Throttle air back to reduce heat output, went to bed.
Glass is clean, draft is probably on the low side (not very cold last night), burned down to ash in the morning. Solid 12 hour burn.

Maybe cut air back to early?
Need to check MC.
View attachment 317704
Which company did you buy it from? I just bought the metal from Midwest Hearth so I have an extra one. Up until this point have you been happy with the metal cat?
 
This weekend was the first time I've burned three days straight. Friday and Saturday went very well, cat typically hung around 1050 to 1150 and STT stuck right around 450 with 50% air most of the time. The challenge I ran into was Saturday night. I did a hot reload with cat around 700 with a 3/4 full load of wood. Hit the bypass right away, air at 50% until the cat hit 1000 then dialed the air down to 10%. Cat slowly rose to 1550 (where I put the air at 0%) and hung there for awhile then slowly dropped over a few hours. As the cat dropped, the STT kept going up and hung around 675 for a long time. Again, air is at 0% but there was a decent amount of flame in the box that kept the STT pretty high on a 0% air setting. I would have anticipated a much lower STT temp with the air at 0% and minimal visible flame. What don't I understand?

I did the same thing last night but I only put two splits in (I had 5 splits Saturday night) and basically the same result. Cat peaked at 1350 with the smaller load but as the cat dropped STT kept going up, decent amount of flame and STT temps hung around 650+ for a long time air at 0%. A few times STT was pushing 700.

Also, STT I was measuring with an IR gun. It was throwing off some major heat.
 
Maybe 10 minutes total. Was up there. Then dropped down to 1400. Then slowly back up. Then back down to cruise temps
This is what I would call my B wood. Smaller and odd shaped splits. I could pack the box tighter and probably keep the cat temps down a little more
 
Which company did you buy it from? I just bought the metal from Midwest Hearth so I have an extra one. Up until this point have you been happy with the metal cat?
I bought from Midwest hearth. So far I have been very happy, it seems to be holding up better structurally than a ceramic cat and it seems to be less "active". My perceptions is I had fewer overtemp events with it. However it it only lasts 1/2 a season I will be less happy with it.... to early to tell yet.

I also have a spare ceramic cat laying around with 1/2 a season on it (already showing some signs of structural distress), may throw that in next and see how it behaves.
 
This weekend was the first time I've burned three days straight. Friday and Saturday went very well, cat typically hung around 1050 to 1150 and STT stuck right around 450 with 50% air most of the time. The challenge I ran into was Saturday night. I did a hot reload with cat around 700 with a 3/4 full load of wood. Hit the bypass right away, air at 50% until the cat hit 1000 then dialed the air down to 10%. Cat slowly rose to 1550 (where I put the air at 0%) and hung there for awhile then slowly dropped over a few hours. As the cat dropped, the STT kept going up and hung around 675 for a long time. Again, air is at 0% but there was a decent amount of flame in the box that kept the STT pretty high on a 0% air setting. I would have anticipated a much lower STT temp with the air at 0% and minimal visible flame. What don't I understand?

I did the same thing last night but I only put two splits in (I had 5 splits Saturday night) and basically the same result. Cat peaked at 1350 with the smaller load but as the cat dropped STT kept going up, decent amount of flame and STT temps hung around 650+ for a long time air at 0%. A few times STT was pushing 700.

Also, STT I was measuring with an IR gun. It was throwing off some major heat.
Hmmm.... this all sounds very familiar.....

Some thoughts on things you might try differently (remember I do not have the answer, only possibilities)
  • Don't reload at cat temps >500..... Hot reload is where I see a lot of overtemp cat events.
  • With lots of fresh soft wood and low air you were probably generating a ton of smoke, a lot of fuel for the cat.
    • Try smaller loads or leave the cat bypassed a bit to burn off the bark and soft wood....
  • Try increasing the air after you hot reload and engage the cat, that might give you a cleaner primary burn and less fuel for the cat. After the bark and stuff burns off slowly close the air back down. Of course you are going to get roasted out..... open a window.
  • Try raking coals to the front or the back, I have occasionally has success with both methods, I think most folks recommend raking to the back.
No definitive answers here.... sorry. Let me know if anything works for you....

P.S. This where we might have different results from the Encore crowd. Defiants have a bigger firebox but the same refractory / cat, I suspect we are generating more smoke (due to more fuel) and trying to process that through the same size cat.....
 
Hmmm.... this all sounds very familiar.....

Some thoughts on things you might try differently (remember I do not have the answer, only possibilities)
  • Don't reload at cat temps >500..... Hot reload is where I see a lot of overtemp cat events.
  • With lots of fresh soft wood and low air you were probably generating a ton of smoke, a lot of fuel for the cat.
    • Try smaller loads or leave the cat bypassed a bit to burn off the bark and soft wood....
  • Try increasing the air after you hot reload and engage the cat, that might give you a cleaner primary burn and less fuel for the cat. After the bark and stuff burns off slowly close the air back down. Of course you are going to get roasted out..... open a window.
  • Try raking coals to the front or the back, I have occasionally has success with both methods, I think most folks recommend raking to the back.
No definitive answers here.... sorry. Let me know if anything works for you....

P.S. This where we might have different results from the Encore crowd. Defiants have a bigger firebox but the same refractory / cat, I suspect we are generating more smoke (due to more fuel) and trying to process that through the same size cat.....
I didn’t struggle too much with the Cat temps. It got high Saturday night but stayed south of 1600.

Why is there so much flame activity and STT pushing 700 with air at 0%?
 
Hmmm.... this all sounds very familiar.....

Some thoughts on things you might try differently (remember I do not have the answer, only possibilities)
  • Don't reload at cat temps >500..... Hot reload is where I see a lot of overtemp cat events.
  • With lots of fresh soft wood and low air you were probably generating a ton of smoke, a lot of fuel for the cat.
    • Try smaller loads or leave the cat bypassed a bit to burn off the bark and soft wood....
  • Try increasing the air after you hot reload and engage the cat, that might give you a cleaner primary burn and less fuel for the cat. After the bark and stuff burns off slowly close the air back down. Of course you are going to get roasted out..... open a window.
  • Try raking coals to the front or the back, I have occasionally has success with both methods, I think most folks recommend raking to the back.
No definitive answers here.... sorry. Let me know if anything works for you....

P.S. This where we might have different results from the Encore crowd. Defiants have a bigger firebox but the same refractory / cat, I suspect we are generating more smoke (due to more fuel) and trying to process that through the same size cat.....
I agree here. More wood and smoke more fuel for sure. And I would say the Cat for the encore is undersized for the stove. It's definitely undersized in my opinion for the defiant.

I tend to hot reload around 600 cat temp
 
I didn’t struggle too much with the Cat temps. It got high Saturday night but stayed south of 1600.

Why is there so much flame activity and STT pushing 700 with air at 0%?
If your STT is getting to 700 at 0% air, you need to find out why.
Unless you were burning really small dry would, the reasons could be.
-Overly dry wood softer woods.
-Gaskets are not sealed well, need adjusting. Do the dollar bill test.
-You left a door open. Ashpan, front door, something was open possibly.
-The flapper that closes down the air was hung up. (this happened to me). Go back and forth a few times or crawl behind the stove and have someone move that flapper. You should see it close and open when someone moves the handle.

Keep in mind that there are air inlets that you cannot control, so that the stove can retain a minimum EPA rating.
 
If your STT is getting to 700 at 0% air, you need to find out why.
Unless you were burning really small dry would, the reasons could be.
-Overly dry wood softer woods.
-Gaskets are not sealed well, need adjusting. Do the dollar bill test.
-You left a door open. Ashpan, front door, something was open possibly.
-The flapper that closes down the air was hung up. (this happened to me). Go back and forth a few times or crawl behind the stove and have someone move that flapper. You should see it close and open when someone moves the handle.

Keep in mind that there are air inlets that you cannot control, so that the stove can retain a minimum EPA rating.
I would agree, I need to find out why.

I was burning all Ash with a MC of 12% on fresh split face.
 
I would agree, I need to find out why.

I was burning all Ash with a MC of 12% on fresh split face.
12% seems too low, but others may have more experience here on how that works out on VC stoves. If I put really dry stuff in, the stove blazes but I can lower it down to keep the stove below 550 or 500.
 
I didn’t struggle too much with the Cat temps. It got high Saturday night but stayed south of 1600.

Why is there so much flame activity and STT pushing 700 with air at 0%?

Again this is all just my opinion:

1550 is pretty hot.... IMO. Others may disagree..... But time is a factor as well, if you were hung at 1550 for hours then I would say that was a borderline overtemp event, if it was for 5-10 minutes then no big deal.... What drives me crazy is the cat goes to 1600+ and reducing the air to 0% has no effect..... very frustrating.

I suspect that the secondary flow was supporting combustion of all the fresh, soft wood (hence the flame activity) and lots of smoke for the cat to eat. The temps were likely driven by the cat/smoke, not the primary combustion. This is one of my complaints about the design, you can't control the secondary airflow directly and if it promotes primary combustion it leads to loss of control.

I assume you checked your primary air flapper? Was it fully closed with temps > 700? I reach behind the stove and pull the wire a bit just to check and see if it is full closed.

Raking the coals to either front or back might help, it will slow down how fast the soft wood goes up by burning from front to back or back to front. An even bed of really hot coals will cause the whole load to go up at the same time and the soft wood burns easily, till you get to the heartwood. And with no primary air it will generate lots of smoke for the cat.
 
Again this is all just my opinion:

1550 is pretty hot.... IMO. Others may disagree..... But time is a factor as well, if you were hung at 1550 for hours then I would say that was a borderline overtemp event, if it was for 5-10 minutes then no big deal.... What drives me crazy is the cat goes to 1600+ and reducing the air to 0% has no effect..... very frustrating.

I suspect that the secondary flow was supporting combustion of all the fresh, soft wood (hence the flame activity) and lots of smoke for the cat to eat. The temps were likely driven by the cat/smoke, not the primary combustion. This is one of my complaints about the design, you can't control the secondary airflow directly and if it promotes primary combustion it leads to loss of control.

I assume you checked your primary air flapper? Was it fully closed with temps > 700? I reach behind the stove and pull the wire a bit just to check and see if it is full closed.

Raking the coals to either front or back might help, it will slow down how fast the soft wood goes up by burning from front to back or back to front. An even bed of really hot coals will cause the whole load to go up at the same time and the soft wood burns easily, till you get to the heartwood. And with no primary air it will generate lots of smoke for the cat.
I was burning ash and I did check the primary flapper which was sitting completely closed. It wasn’t the best feeling when I’m fully closed and couldn’t lower the STT temp as quickly as I would like.
 
I was burning ash and I did check the primary flapper which was sitting completely closed. It wasn’t the best feeling when I’m fully closed and couldn’t lower the STT temp as quickly as I would like.
I hear you..... been there many times.

I burn a lot of ash, red oak and occasional birch. Ash is the most benign in my experience. Red oak seems to give me more overfires....