How quantity of lump affects temp...

I have noticed that lump size affects temps greatly. A huge pile of big pieces will breathe easily and can build a monstrous flame. For low and slows, I try to add a lot of small pieces to fill the cracks that would otherwise be filled with air. I notice a big difference with this factor.

GrateEggspectations said:

I have noticed that lump size affects temps greatly. A huge pile of big pieces will breathe easily and can build a monstrous flame. For low and slows, I try to add a lot of small pieces to fill the cracks that would otherwise be filled with air. I notice a big difference with this factor.

This is true.  Air flow can alter this equation between L & S or ripping hot independent of lump size.  Vents wide open, unless you’re full of dust gets one a hot fire.

Slippy said:

bgebrent said:

Air flow is the primary driver of temps.  You must of course have a cumustible (lump) but the amount of lump matters more for the length of the cook more so than the temp. Also how you light the fire plays a role(1 spot or multiple).  I think you’ve answered your question.

The "how you light" comment is interesting. Have any tips on which ones work best in certain situations? 

For L & S light one spot center to front center.  Let it establish then set your vents.  For 350-400 cooks light 3-4 spots.  How long you leave vents and lid open also affect your temps.

I will chime in and say and agree that lump size matters as well. As far as lighting the fire in relation to temp, the I use a 1600 degree weed burner to fire up—all the time. For L&S it gets a quick half throttle in the center. For steaks and pizza I give it right to her until the top is cherry red. Maybe 2-3 minutes or so. To me the way you light is not the issue, it’s how much lump you start. It takes some practice. Trust me , I had plenty of them get out of hand with this method in the beginning. 

It comes down to carbonization more than size of the lump.  You'll get bigger flames off lower carbonized wood because of the volatiles, but once they're gone and the carbon lights off and that burns hotter than anything else.  Carbon is extremely porous, so the oxygen gets in everywhere and it burns inside and out.

stlcharcoal said:

It comes down to carbonization more than size of the lump.  You'll get bigger flames off lower carbonized wood because of the volatiles, but once they're gone and the carbon lights off and that burns hotter than anything else.  Carbon is extremely porous, so the oxygen gets in everywhere and it burns inside and out.

To a point, I exclusively use your charcoal and (as with any natural lump) the fines in the bottom of the bag will clog the air holes  in the bottom of the charcoal grate... sure more carbonized charcoal is better but if the airflow is blocked than no air equals no combustion. I'm starting to think sorting lump is the way to go, kind of like kindling to start a fire with big logs...

BGEChicago said:

stlcharcoal said:

It comes down to carbonization more than size of the lump.  You'll get bigger flames off lower carbonized wood because of the volatiles, but once they're gone and the carbon lights off and that burns hotter than anything else.  Carbon is extremely porous, so the oxygen gets in everywhere and it burns inside and out.

To a point, I exclusively use your charcoal and (as with any natural lump) the fines in the bottom of the bag will clog the air holes  in the bottom of the charcoal grate... sure more carbonized charcoal is better but if the airflow is blocked than no air equals no combustion. I'm starting to think sorting lump is the way to go, kind of like kindling to start a fire with big logs...

Kick Ash Basket or another replacement fire grate is the best way to fix that with any brand.  We used to manufacture a replacement fire grate.....sold thousands of them.  The kamado have the funnel shaped firebox ending up on a flat plate is not a very good setup for getting ash into the pan.  Ash doesn't flow and there's nothing to agitate it.  Unless it's above the hole, there is a good chance it's not going through.  Some sort of wire grate or basically that doesn't have any flatness to it, directs the ash past the barrier and let's gravity do the work and fall into the ash pan.  Of course, higher the carbonization less ash.

To your point about the airflow, works the other way too....more open grate, more holes or surface area for the air to flow through.

Don't sort lump, get a kick ash basket and just dump the bag in.  When you start getting to the fines at the bottom of bag, switch over to a new bag to fill up to the fire ring.  Then use the fines to top dress it around the outer edge.  I use the whole bag everytime......and I'm not taking home good bags either.  I get the ones that fall off, get run over by a forklift, or just don't look right.

In addition to what was said above about putting the small pieces of lump on top, I make sure to watch the volume of lump. If I'm doing a reverse sear, I can get by with using the divider in the KAB with not much lump. Keeps the temperature low for the beginning, then set the vent wide open and dome open. I only need high temps for a bit, and keeps me from burning a lot of lump.

However, if I'm doing a pizza, I fill to at least the top of the fire box, if not the fire ring. I need more lump to keep the temps up longer (450* for a 12 minute cook).

BGEChicago said:

stlcharcoal said:

BGEChicago said:

stlcharcoal said:

It comes down to carbonization more than size of the lump.  You'll get bigger flames off lower carbonized wood because of the volatiles, but once they're gone and the carbon lights off and that burns hotter than anything else.  Carbon is extremely porous, so the oxygen gets in everywhere and it burns inside and out.

To a point, I exclusively use your charcoal and (as with any natural lump) the fines in the bottom of the bag will clog the air holes  in the bottom of the charcoal grate... sure more carbonized charcoal is better but if the airflow is blocked than no air equals no combustion. I'm starting to think sorting lump is the way to go, kind of like kindling to start a fire with big logs...

Kick Ash Basket or another replacement fire grate is the best way to fix that with any brand.  We used to manufacture a replacement fire grate.....sold thousands of them.  The kamado have the funnel shaped firebox ending up on a flat plate is not a very good setup for getting ash into the pan.  Ash doesn't flow and there's nothing to agitate it.  Unless it's above the hole, there is a good chance it's not going through.  Some sort of wire grate or basically that doesn't have any flatness to it, directs the ash past the barrier and let's gravity do the work and fall into the ash pan.  Of course, higher the carbonization less ash.

To your point about the airflow, works the other way too....more open grate, more holes or surface area for the air to flow through.

Don't sort lump, get a kick ash basket and just dump the bag in.  When you start getting to the fines at the bottom of bag, switch over to a new bag to fill up to the fire ring.  Then use the fines to top dress it around the outer edge.  I use the whole bag everytime......and I'm not taking home good bags either.  I get the ones that fall off, get run over by a forklift, or just don't look right.

Mixing top of the new bag with the bottom of an old bag... should of thought of that before.... Thanks for the tip!

I know a few things about thermodynamics.....especially when it comes to charcoal.

Trust me, when you get that basket or another grate in there, you'll see the size thing really doesn't matter on highly carbonized lump.  It's the surface area you cannot see that is fueling the fire--and that's surface that air cannot get to if the lump is not properly carbonized (it's still wood, thus full of tars/liquors.)  Air doesn't need those big gaps around the lump when it's basically getting sucked into the lump like a sponge.

Ours on average is 250 m2/g  (a piece the size about the size of a golf ball has the surface area of a tennis court.)  If it's not 80%+ carbon, that accessible surface area is drastically lower because of all the pours being plugged up.  That's why it takes so long to light, and there's so much white smoke.

Don't use a cheap IR gun.