Different burning techniques

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I have been having some good results running low air settings the past week. I have avoided Cat temps > 1550 (typical is 1000 - 1400) and back puffing. Thanks @Woodsplitter67 !

Question: After an overnight burn with low air (10-30% open) what is the process for reload?
Assume Cat temps of 300 - 500, STT 300-350, some coals in the firebox but not a thick bed.

Do you:
  • Open the air (with bypass closed) to get the coal bed hot and then reload?
or
  • Add a few splits (with bypass open?) to bring the STT up, then engage the cat to bring it up to 1000 and then reload?
Or.... something else?
I open the air, open the damper and put some smaller splits on get it back up to temp then load her up once I have the cat temps back to 1000
 
I open the air, open the damper and put some smaller splits on get it back up to temp then load her up once I have the cat temps back to 1000
Get Cat temps back to 1000, load it up and - then re-engage the cat immediately and at what % air and for how long?

Last night after loading it up I did not throttle the air back quick enough, 1200 maybe. An hour later the cat started hitting 1550 so I had to open the bypass several times to get it to calm down over the next hour or so. I'm hesitant to let it go beyond 1550.

This morning, standard start up and is now sitting at 1050 with stt 450-550 with 1/3 air. I measure STT behind the griddle and on the griddle with two magnet gauges. Griddle always seems almost ~100 hotter.
 
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I have been having some good results running low air settings the past week. I have avoided Cat temps > 1550 (typical is 1000 - 1400) and back puffing. Thanks @Woodsplitter67 !

Question: After an overnight burn with low air (10-30% open) what is the process for reload?
Assume Cat temps of 300 - 500, STT 300-350, some coals in the firebox but not a thick bed.

Do you:
  • Open the air (with bypass closed) to get the coal bed hot and then reload?
or
  • Add a few splits (with bypass open?) to bring the STT up, then engage the cat to bring it up to 1000 and then reload?
Or.... something else?
You've seen some good burns with doing the technique of getting the cat up to temp on smaller load, then loading up the stove, and then incrementally bringing the air down?
 
I leave the air 100% and like to make sure the load is lit then put some bigger splits on. Not uncommon for me to burn a smaller load at 100% to re-establish a solid coal base.

I usually don't have enough wood in there when restarting to get the cat going nuclear. Once I have the coals re-established and a solid burn and stove temp up then I load 1/2 or full box and get a longer burn going
 
You've seen some good burns with doing the technique of getting the cat up to temp on smaller load, then loading up the stove, and then incrementally bringing the air down?
Yes

So far I am finding when you bring the air down is important, Lately I have been leaving air wide open till I hit ~1200 on the cat. I had issues where I closed down too early (~1000) and the cat temp slowly dropped to 800 and in some cases even 500 ( I think this is what we call a cat stall?)

  • If I have a real hot bed of coals with cat >1000 and then put a full load on it the cat pops right off to 1200+ and I can dial air down in a few minutes.
  • If the cat was <1000 before I put the full load in, I leave the air full open (bypass closed) until the cat gets to 1200 (sometimes this takes 45 -60 min), then start nudging the air down.
I am still figuring this out so take it all as a work in progress..... My hope is to get a repeatable process and then document it with temp plots.
 
I may try this when it gets colder this winter. I normally cut my air all the way, but when it gets down like 10 degrees at night the house is a little chilly.

I might try it during the day to see how the stove reacts first..
Warmer today bruned the load all day at 90% air closed. House stayed at 70. STT 450. Just been putting 3 splits on when the cat hits 800. I think I loaded it three times. Once at 7 Once at 11 Once at 330. Next load I'll pack full and burn 90% closed all night. I find if the air is fully closed I will get some backpuffs especially in these warmer temps
 
Warmer today bruned the load all day at 90% air closed. House stayed at 70. STT 450. Just been putting 3 splits on when the cat hits 800. I think I loaded it three times. Once at 7 Once at 11 Once at 330. Next load I'll pack full and burn 90% closed all night. I find if the air is fully closed I will get some backpuffs especially in these warmer temps


I think the same as @arnermd has stated.. All of our stoves are adjusted slightly different.. I didn't really think about that before. At fully colsed I don't get any backpuffing.. even with a full box. 1/3 air last year was a bad zone. Right now my air is totally of.. moved back from 10% I did get a little backpuffing there.. it may have bee because I had the air roughly half for a while because when I got home the house was a little colder. When im around the house I like loading 2 to 3 times per day because I can keep a more even temp and I like loading on a low cat temperature
 
I have been having some good results running low air settings the past week. I have avoided Cat temps > 1550 (typical is 1000 - 1400) and back puffing. Thanks @Woodsplitter67 !

Question: After an overnight burn with low air (10-30% open) what is the process for reload?
Assume Cat temps of 300 - 500, STT 300-350, some coals in the firebox but not a thick bed.

Do you:
  • Open the air (with bypass closed) to get the coal bed hot and then reload?
or
  • Add a few splits (with bypass open?) to bring the STT up, then engage the cat to bring it up to 1000 and then reload?
Or.... something else?

So if I dont explain this well or don't fully answer the question.. just say so..

If the cat temperature is low like 300 I open the air all the way and bypass.. load some wood.. amount of wood is based on the size of the coal bed.. reestablish draft.. close bypass and engage cat.. Not letting things get to hot.. once cat is roughly 1000.. I open bypass.. load my wood.. maybe a little less then 3/4s.. depending on heat demand.. close bypass and set air.. air automatically goes to less then half.. let it burn

Like the other day when the cat was already 500 with 100%air closed.. Id just drop some wood on that.. and open the air.. no more the half way.. once the cat was like 1000/1100 Id cut the air to where I wanted.. probably 1/3rd air.. let it roll.. maybe drom some more on that if the burn is good and I need to burn longer

When Im reestablishing draft.. im not going crazy.. just enough to get the cat going..

yes/no.. does this help.. or do I suck as a human being
 
So if I dont explain this well or don't fully answer the question.. just say so..

If the cat temperature is low like 300 I open the air all the way and bypass.. load some wood.. amount of wood is based on the size of the coal bed.. reestablish draft.. close bypass and engage cat.. Not letting things get to hot.. once cat is roughly 1000.. I open bypass.. load my wood.. maybe a little less then 3/4s.. depending on heat demand.. close bypass and set air.. air automatically goes to less then half.. let it burn
Yep got it, that's what you have said in the past.

Like the other day when the cat was already 500 with 100%air closed.. Id just drop some wood on that.. and open the air.. no more the half way.. once the cat was like 1000/1100 Id cut the air to where I wanted.. probably 1/3rd air.. let it roll.. maybe drom some more on that if the burn is good and I need to burn longer
OK so for cat temps >500 but less than 1000 you:
  • Open bypass
  • Load on top of the coal bed (just a few splits?)
  • Close the bypass right away?
  • Set air to 50%
  • Let the cat climb to 1000/1100 and then add more wood if needed
    • Does this take 30 - 60 minutes to bring the cat temps up? Or is it quicker than that?
  • Cut air to 30% or less as required
yes/no.. does this help.. or do I suck as a human being
Yes this helpful, thank you.... no you do not suck as a human being..... ;lol

So is it fair to say that you never load the stove full unless that cat is 1000 or greater?

I am thinking this may have been what I was doing wrong all these years..... I would always do a full load with cat <500, run in bypass to bring STT back to 450 and then throw the cat in and let it grind its way up to 1000 then start dialing the air back.
 
Yep got it, that's what you have said in the past.


OK so for cat temps >500 but less than 1000 you:
  • Open bypass
  • Load on top of the coal bed (just a few splits?)
  • Close the bypass right away?
  • Set air to 50%
  • Let the cat climb to 1000/1100 and then add more wood if needed
    • Does this take 30 - 60 minutes to bring the cat temps up? Or is it quicker than that?
  • Cut air to 30% or less as required

Yes this helpful, thank you.... no you do not suck as a human being..... ;lol

So is it fair to say that you never load the stove full unless that cat is 1000 or greater?

I am thinking this may have been what I was doing wrong all these years..... I would always do a full load with cat <500, run in bypass to bring STT back to 450 and then throw the cat in and let it grind its way up to 1000 then start dialing the air back.

So is it fair to say that you never load the stove full unless that cat is 1000 or greater?..... So if the cat is like 1200/1300 i definitely dont add wood and fill the stove.. Burn it down

Im a creature of habit.. I wake up at 5am everyday.. alarm clock hasn't hone off in mor the 10 years.. I load my stove the same.. basically I always let it burn down for a full load..

If there is some wood in the stove like 25%.. Ill just drop.wood on it.. close the bypass.. and dial the air back right away
 
So is it fair to say that you never load the stove full unless that cat is 1000 or greater?..... So if the cat is like 1200/1300 i definitely dont add wood and fill the stove.. Burn it down

Im a creature of habit.. I wake up at 5am everyday.. alarm clock hasn't hone off in mor the 10 years.. I load my stove the same.. basically I always let it burn down for a full load..

If there is some wood in the stove like 25%.. Ill just drop.wood on it.. close the bypass.. and dial the air back right away
What about topping it off. Stove loaded watching a movie. Burns down for say 2 hours. Toss a split on the top before going to bed?
 
What about topping it off. Stove loaded watching a movie. Burns down for say 2 hours. Toss a split on the top before going to bed?

I dont do this either.. I know when Im going to bed, when the stove will need to be filled for an overnight burn.

My stove will be burned down, mostly coals or the wood in the coaling stage.. and what i mean by that is it still could be in the form of a split and past the offgassing point... Then I will add my wood for an overnight.

Everyday that I have run my stove its always burned down. I never add wood to my stove when there is more then a half box or more.. definitely wouldn't consider adding wood to a stove with 3/4s of a load or more.

Once the stove is loaded, air set.. I dont touch anything.. the majority of time. If I need more heat because the house is cold Ill have the air like half and when its warmed up.. Ill cut the air, but the majority of time the stove is left alone to do its thing.

I feel this way about MY stove.. If I start the stove cooler... low cat temps.. on a small/medium bed of coals and drop a load of wood on it.. close the bypass..immediately cut the air.. the stove will bring itself up to its air/fuel ratio that it likes. ..

If I try to reload in the middle of this.. I throw it all off.. Iv done this in the past.. I have my box almost full..the loads just sitting there burning nice and slow.. then open the bypass to add wood .. the box immediately turns into a flaming chit storm.. the balance of the stove now has been changed.. and it backpuffs.. then its master baiting all over the air control.. thats a big no thank you...

Most of the time when the stoves burned down its just to the point where the cat is still in the active range.. the lower end like 700/1000.. then reload

If the cat temperature is like in the 1300s.. I let it burn down.. I dont touch anything.. unless its getting to warm.. then I cut the air more.

I make it a point to initially set the air low and just let it do its thing... which is to sit there and burn lower air settings for long periods of time

For all who read this.. This is just how I run my stove Im not saying its the only way.. This is how Iv burned this fall/early winter.. in the colder times of winter.. Ill burn a little different.. I set the stove based on heat demand..

My burning techniques will change come the end of this month as it gets colder..
 
I must be a loser. All I do is open the door, put wood in, light her up. I have a magnetic thermometer and it stays about 400. House is around 70 all the time. My wood burner is nothing more than a rectangled box made out of cast iron, thats it. No real air control other than cracking the door, but it burns very well. Cats and all the blowers and electric seems WAY too hard.
 
I must be a loser. All I do is open the door, put wood in, light her up. I have a magnetic thermometer and it stays about 400. House is around 70 all the time. My wood burner is nothing more than a rectangled box made out of cast iron, thats it. No real air control other than cracking the door, but it burns very well. Cats and all the blowers and electric seems WAY too hard.


Nope.. but your US stove will certainly run different then ours
 
Ok.. so heres a reload that I just did.. the stove was already running.. cat was already engaged
this was what the stove was..
Stovepipe.. still good draft.. about 2w5 on the outside of the double wall

STT 490.. its a little higher because the box is mostly coals and just burned down

cat temperature 855

picture of what the box looked like and the air cut back all the way

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From the post above.. with the stove in those EXCAT CONDITIONS..

All I did was open the bypass.. load wood.. immediately closed the bypass.. I never touched the air.. it was left colsed the entire time..
Now my STT is 380
cat temperature 1206 and hanging there
this what I was doing to the box.. just added some wood.. not a ton.. in total was 3 splits

So why did my STT drop moe the 100 degrees.. because the STT is not exposed to the coal bed.. theres a bunch of wood now sitting on it

in the past Iv shown my STT with the air all the way back and for some of you the read it thought it was a little high.. its high because.. theres no wood in it.. its all coals.. ready for the next reload..

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Isn’t immediately closing the bypass on a fresh load of wood bad for the cat? Seems like a fresh relatively cool load of wood could send cool smoke into a hot 800 degree cat and cause thermal shock?
 
Isn’t immediately closing the bypass on a fresh load of wood bad for the cat? Seems like a fresh relatively cool load of wood could send cool smoke into a hot 800 degree cat and cause thermal shock?

Its not cool at all.. its sitting on a coal bed.. sure the cat temperature will drop some.. maybe 50 degrees while the bypass is open.. immediately closing the bypass and watching the cat slowly go up is not thermal shock..

A cold cat and an extremely hot stove would be.. like at a cold start.. cat temperature of 109.. and the stove like 650 or more with high draft.. closing the bypass on something like that would probably shock the cat

My cat is metal.. not super worried.. ceramic cats get brittle.. another advantage of a metal cat..
 
Isn’t immediately closing the bypass on a fresh load of wood bad for the cat? Seems like a fresh relatively cool load of wood could send cool smoke into a hot 800 degree cat and cause thermal shock?
I was having the same kind of thoughts and I have heard this concern before (I think my manual actually says to leave it in bypass for a while to char the load and minimize water vapor / thermal shock).

However..... whenever I close my bypass I never see the cat temps crash, they either go up, or slowly drop.

Opening the bypass will cause the cat temps to crash, for obvious reasons....
Edit: Actually I just checked my data from this morning burn, had a rippin hot bed of coals, cat was at 950, I opened bypass to add 4-5 splits (3/4 load) and the closed the bypass. Cat only dropped about 60 deg F.....

My data indicates opening the bypass is more likely to cause thermal shock than closing it.
 
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@Woodsplitter67 loaded the stove before going to work yesterday and worked great. Came home house was still 67°. Cat at 450 stove around 300, solid bed of coals. Tossed a couple small splits on and got it back nice and hot and house was back to 72 in no time. Going to do the same thing again today. Much easier getting the house from 67 to 70 versus 60-70
 
@Woodsplitter67 loaded the stove before going to work yesterday and worked great. Came home house was still 67°. Cat at 450 stove around 300, solid bed of coals. Tossed a couple small splits on and got it back nice and hot and house was back to 72 in no time. Going to do the same thing again today. Much easier getting the house from 67 to 70 versus 60-70


Thanks for rhe heads up.. Super glad it worked out. I normally do a 3/4 load before going to work when its cold out.. It works out great.. I load the stove and set the air back.. let it offgass.. she turns it all the way back when she leaves.. I come home. add wood.. glass is normally clean. You are correct.. doesn't take long to get the house back up to temp..
 
Really curious about you pipe temps. I have the Auber probe 18 inches up from stove collar. When my cat is around 1500 my inner temps are @ 800 +. I don’t see how its possible to be only 360 Unless my stove runs seriously hot.
so the burn is starting to settle in.. the STT will be low as the box has a bunch of wood in it getting up to temperature

SST is 375 cat temp1434 stove pipe is on the out side 280.. inside 360 ish

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Really curious about you pipe temps. I have the Auber probe 18 inches up from stove collar. When my cat is around 1500 my inner temps are @ 800 +. I don’t see how its possible to be only 360 Unless my stove runs seriously hot.

So I am not measuring the gasses..
 
Really curious about you pipe temps. I have the Auber probe 18 inches up from stove collar. When my cat is around 1500 my inner temps are @ 800 +. I don’t see how its possible to be only 360 Unless my stove runs seriously hot.
When my cat is 1500+ the flue gasses are definitely over 800. The highest I have had (this is not a competition I want to win) is when my cat hit almost 1800 the flue was over 1200. I ended up pulling out splits to get that under control. Only happened to me once.