temp management using vents

[EricD]

Curious how many of you guys use the top vent for temp management.  I read somewhere to keep the top vent wide open and use the bottom vent to adjust the temps.  I've done low and slow and hot and fast cooks using this theory with good results.  But I read a post earlier that someone had suggesting closing the top vents to keep the heat up.
So, what is your 'rule of thumb' for temp control?

[Bugman]

I'm curious to hear about this too.  Have always read to keep the top wide open to prevent stale smoke from building up.  But better temp control is always good

[1buckie]

Weber 1958 brochure.....courtesy BBQ Miller.....

http://weberkettleclub.com/forums/weber-kettles-accessories/1958-weber-bar-b-q-kettle-grill-12-page-original-brochure/

"Damper in cover always remains open when cooking"

It's the way they were designed, but people do crimp down the lid vent sometimes....
I rarely do, 'cause I want the fire to exhaust clean.......choking down the burn from above can lead to a sluggish fire & creosote buildup......certain circumstances, like when moving from high heat to a high-medium heat, it can be helpful.....

[Bugman]

Hmm, when I click your link it takes me to a post about a happy cooker...  Odd!  I'll try from my computer later.

[1buckie]

Odd, here's the title & it works fine here......

1958 WEBER BAR-B-Q KETTLE GRILL 12-page original brochure

[Bugman]

Must be a Tapatalk fluke.  Works when I cut and paste it.  Thanks Buckie!

[Johnpv]

When I'm just straight up grilling I keep the top vents wide open.  When I'm smoking on the kettle that's a different story.  They get adjust as needed then, some times it's just too windy, or too something else, and those top vents a long with the bottom ones need to be adjusted to dial in the temp I want. 

[EricD]

@1buckie That brochure is pretty cool!  Nice find. Thanks.

[Harleysmoker]

Top vent always wide open whether low and slow smoking or hot and fast.

[austin87]

I keep the top vent at least half open, and always more open than the bottom vent - it's my untested theory as long as the fire can exhaust faster than air can be pulled in through the lower vent that you won't get creosote buildup. It's not uncommon (for me) for the lower vent to be about 1/4 open and the top vent to be 1/2 open while trying to keep temps down down in the 250ish range when doing a minion setup.

Yes in an ideal world the top vent is full open all the time, but I find sometimes it helps keeps temps low if it's slightly choked.

[ckf]

I always keep my top vent wide open and use the bottom vent to adjust temperature.

[Grizz]

Huh!  I've been doing it backasswards!  I've been keeping the damper open about a quarter and adjusting the temp with the top vent.  I'll have to give it a whirl the other way around.  Live and learn.

[EricD]

things like that ^ are why I love this site!  Always something new to learn!!

[Troy]

definitely try to keep top vent open as much as possible

for low and slow, sometimes i'll close it 1/4 (still 3/4 open) - but that's the max unless there's an emergency.

for grilling, always wide open.

creosote happens when the fire is over choked, this can happen from exhaust build up, or lack of oxygen (essentially the same thing)
The best way to prevent is keep lit fuel to a minimum, and let exhaust out as quickly and cleanly as possible.

I run my WSM clone with the bottom vents nearly completely closed and top vents completely open.
If the temps get too hot (if i start with too much lit, or if i keep the lid off for too long), I have no choice but to choke the fire buy cutting off the exhaust. Although I'd rather just let it run hot than do that.
This is why i run with an empty water pan. If shit gets out of control, i can add water mid-cook to bring temps down without choking the coals.

[Jammato]

in my experience,I use the bottom vents for temp management, and the tops for air movement,

Now having said that, they both affect each other, so you need to do some experiments

as always I say, keep notes of every cook, then after reading them you can make changes, and have a record of what changes. After a few cooks it becomes natural.