Question on vent management

Dwain Pannell

TVWBB Hall of Fame
I control heat by closing upper and lower vents. Three open on bottom = top 100% open. Two open on bottom = top ~25% closed (~75% open). One open on bottom = top ~50 % closed.

Like Chris said after a while you just kinda know your cooker.
 

JWorden

TVWBB Member
For me if I want about 250 I close the bottom vents to 1/3 open and the top 3/4 open.

I start closing the bottom around 225 and then the top if the temp starts going over 240.

I light it with about 10 coals and measure the temp through the side grommet not the top grate.
 

MartinB

TVWBB Pro
that openings are affected by how much coals you start with as well so you got to be consistent on that to be consistent with the vent openings..... I.e. a half chimney is way different than a 1/4 or a full chimney.

Just don't stress about the temperature too much anywhere from 225 to 275 is really about the same thing. Except for time. Higher temperatures will develop better bark. Just let it run where it wants to run, tweak it slowly.

I use an ATC though now so..... It makes it so much easier..... So much easier.
 
I leave the top 100% open all the time.

Minion start with about 30 lit briquettes and hot H2O in the pan for an overnight cook. I start with the bottom vents open until temp gets to near 200, then I dial them to about 25% open for all three.

I go to bed. Temps will stay in the 225-75 area.

Did this last weekend for a butt that stayed on over 12 hours. I never touched the vents again, even the next morning.

I used to chase the temp, constantly fooling with thermometers and vents. Then I achieved much inner peace when Gary Wiviott's "Low & Slow" book convinced me to set it and forget it.
 

Jim C in Denver

TVWBB Super Fan
Going on 15 hours between 230-265 -- top vent 100% open, one bottom vent open the width of a skewer-to-pencil. Plenty of charcoal left. I did give the coals a good stir first thing in the morning to knock some ash off.

Will start opening up #2 and then #3 once the temp starts dropping.

18 WSM, no water, FireDial, #8 pound pork shoulder, KBB.
 

Ron De Hoogh

TVWBB Super Fan
I leave the top 100% open all the time.

Minion start with about 30 lit briquettes and hot H2O in the pan for an overnight cook. I start with the bottom vents open until temp gets to near 200, then I dial them to about 25% open for all three.

I go to bed. Temps will stay in the 225-75 area.

Did this last weekend for a butt that stayed on over 12 hours. I never touched the vents again, even the next morning.

I used to chase the temp, constantly fooling with thermometers and vents. Then I achieved much inner peace when Gary Wiviott's "Low & Slow" book convinced me to set it and forget it.
With the exception of water and the amount of lit charcoal I do the same thing.
 

MichaelM

TVWBB Fan
Just did my first brisket yesterday. While it was so-so, The WSM worked flawlessly. My setup was similar to what others have already noted. Minion method (about ten lit coals) in a full basket, warm water in the pan. Vents fully open until temp reached about 185-ish. All bottom vents then closed to about 1/4" top vent at half closed. Darned thing sat at 225-250 for nearly ten hours without touching anything.
 

M Andreyka

TVWBB Member
Seems like leaving the top vent fully open would use more fuel in the long run, with my ATC I close top vent to about half or less
 

Erik Tracy

TVWBB Super Fan
You can control the fire by adjusting the top vent. Search on here and you will see discussions of that topic which cite WSM champ Harry Soo as being in favor of adjusting at the top.

That discussion is where I got my preferred method (also from Harry) -- run the WSM with just one vent open on the bottom and the top open too. Then eventually start opening up #2. And then later start opening up #3. For me, it is easier to keep track of one at a time rather than all three at 1/4, then 1/2, then 3/4...

But the norm on here seems to be to adjust primarily with the bottom. Some folks say that adjusting via the top in some way messes with the flow of good smoke. On that, I have no idea. There's also chatter about how you'd use the top vent differently if you use an ATC.

And then there's this from the Weber website (mostly directed at kettles): "We suggest leaving the bottom dampers fully open and using the top lid damper to control the temperature." Could be that on a kettle, you might be more worried about falling ash clogging up the air flow of a slightly cracked bottom vent. So better to leave the bottom open and just adjust the top.

Could be that folks use the bottom for the WSM simply because there are three vents and so there's a lot more fine adjustments you can make. And ashes blocking the three WSM vents is not a worry.
Hmm - I took Harry Soo's class 2 years ago and he said NOT to mess with the top vent - just the bottom ones.
 

MitchS

New member
Just did my first brisket yesterday. While it was so-so, The WSM worked flawlessly. My setup was similar to what others have already noted. Minion method (about ten lit coals) in a full basket, warm water in the pan. Vents fully open until temp reached about 185-ish. All bottom vents then closed to about 1/4" top vent at half closed. Darned thing sat at 225-250 for nearly ten hours without touching anything.
How many briquettes did you use in total? Lit from the chimney and the amount in the holder (inner ring on the coal grate)? Did you add any throughout the cook? I'm asking because I have a 1/2 chimney with lit coals added to an almost full basket and it lasts about 5-hours tops. Not sure how I would handle a long cook.
 

Ron De Hoogh

TVWBB Super Fan
I have read different opinions on controlling the temps using the top vent or not and for me I leave it all the way open,but if you don't get any sooty flavors from closing the top vent I say use however you want.
 

Bob Bass

TVWBB Guru
Harry used to say to manage temp with the top vent. Link below.

More recently, he says use the bottom.


Actually that is incorrect. There was only a SHORT period of time where he was playing around with the Top Vent.
I was a student in Harry's class back in January 2012.
 

CaseyMcC

New member
How many briquettes did you use in total? Lit from the chimney and the amount in the holder (inner ring on the coal grate)? Did you add any throughout the cook? I'm asking because I have a 1/2 chimney with lit coals added to an almost full basket and it lasts about 5-hours tops. Not sure how I would handle a long cook.
I have used 12-15 lit briqs on a filled coal ring. It takes a little while to come to temp, but it holds well and lasts hours without having to add more coals.
 

Jim C in Denver

TVWBB Super Fan
Bob -- I adjust using the bottom vents fwiw. But the following is still on Harry's website. There's obviously more than one way to get to Baltimore:


Of the three components I mentioned: intake, fuel choice and amount, and the exhaust, the most effective component to maintain constant temperature is not the intake nor the fuel. It’s the exhaust. Many beginners I come across are not aware of that. All seasoned pitmasters know how to intuitively draft their pit using “clean” smoke to color and flavor their barbecue meats. The draft refers to the vacuum effect when you open or close the exhaust vent of your pit.

When you open the exhaust vent on the WSM, you allow hot air to leave the pit and this creates a vacuum suction to draw air in from the bottom intakes. Thus, by skillfully manipulating the top vent, you can control your WSM like a pro. Many beginners constantly fiddle with their intake dampers in hopes to maintain a constant temperature with less success than leaving the bottom vents untouched and fiddling with the top vent to control the draft within their WSM. In future articles, I’ll address the mechanics of damper control on the WSM (e.g., old school versus automated blower systems) and the science on dirty smoke, white smoke, clean smoke, blue smoke, sour smoke, etc. For now, just give my technique a try and see if it works for you.
 

MichaelM

TVWBB Fan
How many briquettes did you use in total? Lit from the chimney and the amount in the holder (inner ring on the coal grate)? Did you add any throughout the cook? I'm asking because I have a 1/2 chimney with lit coals added to an almost full basket and it lasts about 5-hours tops. Not sure how I would handle a long cook.


No idea how many were in the charcoal ring... pretty full is the best I can offer.

The chimney had 10 lit briquettes, dropped into a can in the center of the charcoal ring.

In my limited experience, a half a chimney of fully lit briquettes dumped on a nearly full charcoal basket will runaway pretty easily, Even so, it should last well more the 5 hours.
 

Chris Allingham

Administrator
Staff member
I know that no one cares what the maker says, but just for a complete picture I will include their instructions here, from pages 6-7 of something called "the owner's manual". :) Emphasis is mine.

BEFORE LIGHTING

Blah, blah, blah...

D) Open all vents on the bottom of the bowl.

SMOKING INSTRUCTIONS

Blah, blah, blah...

D) Pick up the lid by the handle, place it on top of the center section and open the vent on the lid.
E) The vents are used to regulate heat within the smoker. Opening vents increases temperature and closing vents decreases temperature.

Temperature of 250*F is ideal for most meats. Check the temperature every 15 minutes and open or close the bottom vents as needed until you achieve and maintain your target temperature.

Blah, blah, blah...

H) When smoking is completed, brush grates with a grill brush or crumpled aluminum foil to loosen any debris and close all vents to extinguish the coals.
 

Jim C in Denver

TVWBB Super Fan
The chimney had 10 lit briquettes, dropped into a can in the center of the charcoal ring. In my limited experience, a half a chimney of fully lit briquettes dumped on a nearly full charcoal basket will runaway pretty easily, Even so, it should last well more the 5 hours.

Same here. I always fully load the ring with unlit no matter what I'm cooking. If it doesn't get used today, it will get used next time.

Depending on weather and what I'm cooking, I only light 10-20 to start the Minion burn. 20 is about half of the compact/small Weber chimney. Half of the full size chimney is like 50 briquettes. That's fine for hotter/faster, but too much lit for low/slow.

With a dry pan/diffuser plate, my 18 will go about 14+ hours at 250-ish. A few hours less if using water.
 

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