Understanding Temp Control in a KK

[DennisLinkletter]

 Charcoal always burns at the maximum volume for the allowed airflow.. Combustion requires three things, fuel.. ignition and oxygen/air..  The first two are covered so always remember that temperature is simply airflow.

Airflow in a Komodo Kamado is very different than other charcoal grills because there is no gap between the firebox and body or holes in the firebox that permit air to bypass the charcoal.   This means that when exhaust exits your chimney the vacuum that is created pulls/sucks air in through the front draft door and forces it all through your charcoal.  In all other charcoal grills most of the air goes around the charcoal because air always take the path of least resistance.

  My favorite analogy to help understand the lower draft door settings is a garden hose.. the diameter (to some extent) determines how the volume which can go through the hose but the pressure not the diameter of the hose is the most important factor.   The pressure in your grill is the vacuum.  The more freely the hot air exits the grill, the more vacuum is created, the more baffled and restricted the exhaust, the less vacuum.   Because all air is forced through your charcoal, anytime you have a stable temperature, simply take a mental or physical note of your top and bottom settings..  they will always create the same temperature.

The large volume of dense refractory hot face has high thermal mass.. this creates uniform convective heat and stability. The large volume of insulation prevents heat loss, this also means you can't reduce temps quickly once heat soaked. Better to preheat the grill slowly than to overshoot your target temp.

For 235ºf you want to light about a tennis ball volume of charcoal, open the damper top until it spins free, turn back until the top touches the gasket then move the damper top's ear about 2" only. The lower draft door should be open about a pencil volume at most. Once you have a stable temp you can adjust the lower draft to fine tune.

in other grills the settings change if the density of your charcoal in the basket changes.. more smalls etc because more air will bypass the charcoal.. in your KK anytime you have a stable temp, make a physical or mental note of the top and bottom settings as they will always be the same.. after a handful of cooks on your KK you will find cooking on it very intuitive.

 

[Rak]

Thanks Dennis, very timely!

[wilburpan]

I think Dennis’s point here is important, especially if you’re coming from another brand of kamado:

 

 

For 235ºf you want to light about a tennis ball volume of charcoal, open the damper top until it spins free, turn back until the top touches the gasket then move the damper top’s ear about 2†only. The lower draft door should be open about a pencil volume at most. Once you have a stable temp you can adjust the lower draft to fine tune.

 

For a low and slow cook, the vent settings I wind up using on Smaug are much much smaller compared to vent settings I’ve seen in videos featuring other brands of kamados. Almost shockingly so.

[MacKenzie]

The moral of this story is start with a KK.

[Gnomatic]

 

For a low and slow cook, the vent settings I wind up using on Smaug are much much smaller compared to vent settings I’ve seen in videos featuring other brands of kamados. Almost shockingly so.

 

Agreed.  Just a sliver of an opening on both bents is all a KK needs when going low and slow, even with ambient temps below freezing.

[kjs]

Good information and explanation.

[Pequod]

My 23 also has two lower dampers. I find that I get a wide range of temps with just one turn of the cap and adjusting the left vent alone, keeping the right vent closed. I use the right vent for more precise control at low and slow temps. For example, I get 250 degrees with just 1/4 turn of the top vent and the largest hole on the lower right open. I get 225 with 1/4 turn and the third hole.

Best bet is to spend a day experimenting.

[tomahawk66]

I found the burn in the perfect time to experiment.
I never wrote down the temps and positions but find it very intuitive to get a temperature that I want

Sent from my SM-G935F using Tapatalk

[tony b]

 

Like others have said, spend some time (preferably with an adult beverage) and just keep adjusting the dials and watching what the dome temperature does for a fixed top damper setting. The top damper is more critical than the lower ones for setting temperature, as the airflow through the KK is by vacuum drag, which is dictated by the top damper opening.

[DBQ]

Understood - yes for sure, this is a time for experimenting, thanks all.  Just wanted to make sure I wasn't missing anything obvious - so far so good, I underestimated the amount of charcoal needed for a proper burn-in, so I lowballed myself.  Will test with a fuller basket this weekend and adjust around.  

[Pitou]

Hey guys, this may seem basic but I come from a pellet ceramic smoker that needed no air adjustment...

I'm presently breaking in the KK, I've loaded my basket ans started the fire. I closed the lid, set the bottom vent to 3/4 and top vent to 2 turns, normally on an hibachi grill I would wait till all the coals are white to even think of putting anything on there.... With the KK now the coals are getting hotter but still making the nasty white smoke, I have not reached my first burn in temp of 350-400, looking to keep it there for a couple of hours. 

My point is, the white smoke is still there because the coals are not completely lit and I've been chocking the fire, when do we normally add the meat, when is the kk ready to cook lets say if I'm roasting at 350, I got my temp right about now but the nasty white smoke too??

[Pequod]

You're open way more than you need to be. Kamados work best with very little air flow. For 350, I need only about 1/2 turn of the top vent and then adjust the bottom accordingly. Top vent is your big muscle movement. Bottom vent is tuning within the range set by the top vent. For 500, I need maybe a tad more than 1 turn of the top. 

You'll also want to keep in mind the difference between heat soaked and not and when you need each. Heat soak for long cooks. Don't for quicker cooks like grilling. For your burn in, you are heat soaking. This takes more time for temps to stabilize. 

[Pitou]

OK I've adjusted the damper, the temps is stable at around 375, the damper is at 1/4 turn and the bottom is at the smallest pinhole right side and left side completely closed. 

Now for the white smoke, I could not imagine putting meat right now, but then again I could be wrong

[ckreef]

Once it settles at the target temperature for 20 or 30 minutes the white smoke will go away. How long that takes can depend on the lump you're using. Also you probably got too many coals lit to begin with so they'll need a few minutes to calm down. 

 

[Pitou]

Thanks Charles

6 minutes ago, ckreef said:

Once it settles at the target temperature for 20 or 30 minutes the white smoke will go away. How long that takes can depend on the lump you're using. Also you probably got too many coals lit to begin with so they'll need a few minutes to calm down. 

 

Thanks Charles, good point, it's total different ball game, speaking of the load and having too many coals lit, I did light 3 different areas, that could be the culprit, what do you recommend? Until you mentioned it I never thought this could impact...Very interesting

[ckreef]

1 minute ago, Pascalpro said:

Thanks Charles

Thanks Charles, good point, it's total different ball game, speaking of the load and having too many coals lit, I did light 3 different areas, that could be the culprit, what do you recommend? Until you mentioned it I never thought this could impact...Very interesting

I only lite one spot for all temps. I usually start with the top vent at 3 turns and the bottom vent wide open. Once a draft starts going up through the KK the coals will fire up pretty quickly so be prepared to start closing the vents down. My final vent settings are similar to what others have posted. 

Every once in a while I'll start 2 or 3 spots but that's only when I want a full bed of raging coals. 

[Pequod]

How many spots I light depends on my target temp. One spot for under 300, two to three for 300 to 450. Four for above that. Those are ballpark estimates, not hard and fast. 

[Pitou]

8 minutes ago, ckreef said:

I only lite one spot for all temps. I usually start with the top vent at 3 turns and the bottom vent wide open. Once a draft starts going up through the KK the coals will fire up pretty quickly so be prepared to start closing the vents down. My final vent settings are similar to what others have posted. 

Every once in a while I'll start 2 or 3 spots but that's only when I want a full bed of raging coals. 

Thanks a million Jeff & Charles, I feel like a toddler learning how to walk!! lol

Edited April 2, 2017 by Pascalpro

[Pequod]

39 minutes ago, Pascalpro said:

Thanks a million Jeff & Charles, I feel like a toddler learning how to walk!! lol

No worries. We've all been there. Fortunately, you'll find the learning curve on the KK is extremely shallow. 

[Pitou]

Believe me I know 200% more of it now than a couple of hrs ago. Thanks to this great community!

salute to all of you!

4 minutes ago, HalfSmoke said:

No worries. We've all been there. Fortunately, you'll find the learning curve on the KK is extremely shallow.