Tons of smoke upon startup after a long low burn

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The hottest part of a cat stove during the cruise is the top of the stove around the cat. I'd wager that when you are ramping up a fresh load, with the heat and radiation of big flame in the box, the sides may be quite a bit hotter than at cruise. I can't really test this theory on my stove because of the buffering/lag effect of two layers of stone..but steel stove guys should be able to verify weather this is the case.
I'm not sure we can ascertain the color of the smoke from Rangerbait's picture on the internet. We'd have to be there to say for sure. But to me, it looks kinda heavy and dirty. White, wispy smoke is steam, gray or blue smoke is wood smoke. This creo smoke has an almost brown look to it. When I have a bad 'smoke out the hood' episode (doesn't happen every time) after a long, low burn, there's a thick, billowing cloud of foul-smelling creo smoke blanketing the area like a heavy fog. I mean, birds are falling out of the trees. ;lol I think this is the condensed, concentrated creo on the walls of the stove burning off..hours worth of deposits being burned off in a relatively short period of time. Yes, later in the burn you will still get a little creo smell but I think that even though the majority has burned off the walls, I think the creo-burning continues at a lower level. It's a much worse smell than you would get just burning a few splits at your fire pit.
So if you have company coming over, or the neighbors are out, make sure you burn out your stove beforehand, then throw on some Black Cherry splits and you'll have them saying "What a lovely fragrance, we should get one of those wood-burners!" >>

Remember, all sides of the bk other than the cat dome are either glass or insulated in some way. Just part of the very rear of some models is actual exposed steel. So perhaps your problems are Woodstock problems and not bk problems. I never have brown smoke, just white, blue, or clear.
 
The hottest part of a cat stove during the cruise is the top of the stove around the cat. I'd wager that when you are ramping up a fresh load, with the heat and radiation of big flame in the box, the sides may be quite a bit hotter than at cruise. I can't really test this theory on my stove because of the buffering/lag effect of two layers of stone..but steel stove guys should be able to verify weather this is the case.
I'm not sure we can ascertain the color of the smoke from Rangerbait's picture on the internet. We'd have to be there to say for sure. But to me, it looks kinda heavy and dirty. White, wispy smoke is steam, gray or blue smoke is wood smoke. This creo smoke has an almost brown look to it. When I have a bad 'smoke out the hood' episode (doesn't happen every time) after a long, low burn, there's a thick, billowing cloud of foul-smelling creo smoke blanketing the area like a heavy fog. I mean, birds are falling out of the trees. ;lol I think this is the condensed, concentrated creo on the walls of the stove burning off..hours worth of deposits being burned off in a relatively short period of time. Yes, later in the burn you will still get a little creo smell but I think that even though the majority has burned off the walls, I think the creo-burning continues at a lower level. It's a much worse smell than you would get just burning a few splits at your fire pit.
So if you have company coming over, or the neighbors are out, make sure you burn out your stove beforehand, then throw on some Black Cherry splits and you'll have them saying "What a lovely fragrance, we should get one of those wood-burners!" >>

Damn man, that last paragraph nailed it...and yes, it’s the bird-assaulting brown smoke that I’m getting too. Guess I’ll chalk it up to a known issue, and adjust my technique accordingly. Thanks all!
 
Remember, all sides of the bk other than the cat dome are either glass or insulated in some way. Just part of the very rear of some models is actual exposed steel. So perhaps your problems are Woodstock problems and not bk problems. I never have brown smoke, just white, blue, or clear.
Well, here's a pic of a King interior, and I assume your Princess is of similar construction. Not sure which stove Ranger has. As you can see, smoke can make its way around the interior side baffles and deposit creo on the walls of the box. When Ranger burns his stove on high with a fresh load, it will take longer for the walls to heat up since they are shielded, and he's still seeing the creo smoke burn off an hour or more into the load. The smoke isn't "brown-brown" but there's a different look to it for sure. I'm pretty sure that any cat stove owner has seen it on occassion, not sure why you haven't. Actually it's probably less of a problem on my stove since, if I run a little flame in the box, the sides will be hotter from flame radiation than will the shielded walls of your stove. A BK operator could run flame as well, but it will take more flame to get the sides of the stove as hot due to the baffles, and more heat will be going up the flue.
As an aside, the baffles are probably what allows the BKs to run as low as they do; They concentrate more heat inside the box, allowing for a clean burn at a lower air setting. In addition, the air wash tubes are totally inside the firebox, keeping the incoming air hotter and allowing the cat to stay active at lower burn rates. The baffles are probably also responsible for the lower peak outputs of the BKs in the EPA tests. Not 'alien technology,' just physics. ==c
[Hearth.com] Tons of smoke upon startup after a long low burn
 
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I smoke heavy for about 10 min, then once I engage the by-pass damper I quell the smoke, within 20 min from engaging the by-pass I have very minimal smoke or just vapors.
One a side note, everyday I pass a house on way to and from work that has an older smoke dragon, the smoke is always pouring out of the chimney like in your pic, so your smoke, my smoke, and every other Bk owners smoke pails in comparison.
 
I think @Highbeam and @lsucet have the hookup here. Thanks for the tag @begreen , I had been watching this one.

Clearly challenging conditions, thanks for looking at your stack. I would get at least a verbal warning for that if one of the AQ (air quality) police was in my neighborhood when that happened. I am limited to 20 minutes at 50% opacity on cold starts and reloads per EPA VEE #9. The pic doesn't show enough ambient light to make a certified reading on level 9, but my doorbell would get rung.

I have never burned any Ash, but since you are getting that at 15%MC and under, might be time to step outside the manual.

What I would try in the situation described after a long slow burn is rake all the coals together, toss a couple or 3 splits in there (not four) looking for bigger than a 2x2 but smaller than a 2x6 for cross sectional area. What I would be looking to do is make as much heat as possible (I think to warm the chimney back up) , while making the least smoke possible. So small amount of wood at full throttle, top of the swoosh after closing the cracked door.

With the smoke flowing basically down the side of the pipe, down the roof and out onto the lawn as pictured heating up the stack with a few small splits isn't going to solve everything, but a quick hot burn will get the system heated back up so when the OP puts a full load in there on a bigger coal bed 30-60 minutes later he can hopefully maybe 1) reload with the door open 2) get a good char with the loading door cracked in 60 seconds or less and 3) get the cat engaged with the indicator at least a finger width up in the active zone a few seconds after latching the loading door. From there run on high for _at least_ 30 minutes (because of the short char) and then turn the Tstat down.

I would try that first, running out to look at the stack immediately after combustor engagement. I have found pretty consistently (my install, my wood, blah, blah, blah) that my plume is clean when the combustor probe indicator reaches the first tick mark about 1/4 inch up into the active zone. Below that, doesn't matter what color the combustor is glowing, I got visible smoke from the stack.
 
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I think @Highbeam and @lsucet have the hookup here. Thanks for the tag @begreen , I had been watching this one.

Clearly challenging conditions, thanks for looking at your stack. I would get at least a verbal warning for that if one of the AQ (air quality) police was in my neighborhood when that happened. I am limited to 20 minutes at 50% opacity on cold starts and reloads per EPA VEE #9. The pic doesn't show enough ambient light to make a certified reading on level 9, but my doorbell would get rung.

I have never burned any Ash, but since you are getting that at 15%MC and under, might be time to step outside the manual.

What I would try in the situation described after a long slow burn is rake all the coals together, toss a couple or 3 splits in there (not four) looking for bigger than a 2x2 but smaller than a 2x6 for cross sectional area. What I would be looking to do is make as much heat as possible (I think to warm the chimney back up) , while making the least smoke possible. So small amount of wood at full throttle, top of the swoosh after closing the cracked door.

With the smoke flowing basically down the side of the pipe, down the roof and out onto the lawn as pictured heating up the stack with a few small splits isn't going to solve everything, but a quick hot burn will get the system heated back up so when the OP puts a full load in there on a bigger coal bed 30-60 minutes later he can hopefully maybe 1) reload with the door open 2) get a good char with the loading door cracked in 60 seconds or less and 3) get the cat engaged with the indicator at least a finger width up in the active zone a few seconds after latching the loading door. From there run on high for _at least_ 30 minutes (because of the short char) and then turn the Tstat down.

I would try that first, running out to look at the stack immediately after combustor engagement. I have found pretty consistently (my install, my wood, blah, blah, blah) that my plume is clean when the combustor probe indicator reaches the first tick mark about 1/4 inch up into the active zone. Below that, doesn't matter what color the combustor is glowing, I got visible smoke from the stack.

You know, that’s exactly what I did the past couple of days and it has been a million times better...thanks for all the great tips!
 
Good news. Loading these cat stoves tightly with splits stacked parallel doesn’t really allow the young fire to take off quickly. When building a campfire you stack wood loosely in opposite directions for high air flow. Opposite.

I see two options. Light a pre-fire of loose stacked small stuff or just suffer through some smoke by igniting a full load.

I don’t want to waste the time and effort on a pre-fire.
 
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