Temp control: adjust top or bottom vents?


 

KevinInStL

TVWBB Member
Hey guys, been lurking for a bit, thought I'd finally sign up and post. I have this burning question ;) that's been on my mind, though it is a basic fundamental one.

So this Meathead guy at amazingribs.com https://amazingribs.com/more-techni...up-and-firing/using-vents-control-temperature says to leave your exhaust vent fully open all the time, and control your temps with the intake. He seems like he knows what he's talking about.

But Weber recommends the opposite; leave the intake fully open and control temps with the exhaust. Can't find the page on Weber's site where they make this recommendation, but I know I've seen it before. Apparently I'm remembering correctly because Meathead and a reader discuss this in the comments in the post linked to above.

Which do you do and why? Does it make much difference?

I'm using a newer 22" kettle with the one-touch intake if it matters. No triple daisy wheel intakes here, but would that make a difference? (besides in the convenience of making 1 vs 3 adjustments?)

Thanks,
Kevin
 
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I use the WSM 22 as well. I manage temp exclusively with the bottom vents and leave the top vent alone for the duration of the cook unless there is a fire (which doesn't happen if you clean the WSM properly and are sensible with your fuel.) I had always heard that closing the top vent traps gasses to the point that you get a bitter taste in your bark. I don't know if that is actually true, so let me give you my practical reason for this approach -- I have never needed more than the bottom vents to control temp. Lock em down if you have run away heat, open em up if you are too low, and finesse in between. Cheers.
 
This is one of those discussions that can go on forever, that said; I prefer to use the bottoms with the top wide open.

If you consider using the top for control, anytime you close it 25% you will drop your airflow by 25%. Using the bottom intakes, if you close one 25% it will result in drop of 8% airflow. That gives you you a much more precise mechanism for control.

I tried it using the top but went back to the intakes.
 
I tend to go with the conventional wisdom about leaving the top vent open and using only the bottom vents, but I'm not a purist about it. On rare occasion when I've let the fire get too hot I'll partially or completely close the top vent to get things back under control. Or there's the flip side where I'm basically using the WSM as an oven and can't get it up to the desired temp. One Thanksgiving I had to prop open the top to get enough air flow to keep the charcoal burning hot enough.

Logically, it seems that it's all about air flow. The hot air rises out of the top and is replaced by cool, oxygen-rich air coming in at the bottom. You can restrict or stop this flow with either the top or bottom vents. Air will slow regardless of where the restriction is. That said, bear in mind air can get in and escape through any crack. The door on the WSM is notorious for not fitting very tight and allowing air in. I'm sure we've all seen loads of smoke escaping from where the top of the WSM meets the body. It's hardly a hermetically sealed vessel. So do what you need to do to control the temp.
 
I think he's asking about the kettle and everyone seems to be talking about the WSM. On the kettle I use a combination of both.

On the WSM, I agree with Jay.
 
I think he's asking about the kettle and everyone seems to be talking about the WSM. On the kettle I use a combination of both.

On the WSM, I agree with Jay.

Thanks for pointing that out, Dustin. I didn’t realize he was on the kettle...yep...I was talking about the WSM.
 
Kevin, welcome aboard.

I use the bottom or intake vents on both the kettle and the WSM to control temp.

I use the top only if I am unable to control the temp with the intake. And I use the top and bottom to smother the fire at the end.

YMMV
 
The basic advice is to leave the top open to increase airflow across the meat and adjust the intakes to control the temp. The kettle is a bit of a challenge, since the intake control is fairly coarse (as opposed to the fine controls of the WSM vents). I find that I often have to adjust the top vent on the kettle a bit to maintain temp. One trick I learned was to mark the intake vent control lever at closed, 25% open, 50% and 100%, as shown in the photo. Admittedly, there is some guesswork involved, but it's better than flying blind.

Jeff

Kettle vent by Jeff Hasselberger, on Flickr
 
I think he's asking about the kettle and everyone seems to be talking about the WSM. On the kettle I use a combination of both.

On the WSM, I agree with Jay.

Certainly not ruling out a WSM in the future, but for now you’re correct. I only have a 22” kettle.
 
Do what Jeff said! Mark your “One touch” control arm and you will be able to control things much more comfortably.
I saw that on some “ Hot Smoke Barbecue” Site (something like that) and it was really helpful. It’s a very different skill set from using a WSM, it’s really worth looking at. His chicken technique is interesting too!
Kevin, you have started swimming in a fascinating river of gustatory delights, get strong and never forget...
“Success and Failure when cooking end up in the same place.” Be bold, be brave, eat well!
 
Can't find the page on Weber's site where they make this recommendation, but I know I've seen it before.

My recall is that I read that in their manuals. My WSM manual recommends adjustment of the intake vents to control the burn and the Kettle manual suggests utilization of the lid vent for control. I don't necessarily fully conform to those methods but they are at least good starting points. I rarely use one, but if you use an ATC its manual will most likely suggest a different approach to damper control.
 
I recall that too, but me thinks it was more for smoking or indirect. Standard Weber setup is coals on one or both sides, and the meat on the other side or middle.
Top vent is over the meat or opposite sides of the coals.

Shutting down the top vent slightly for lower temps won't hurt. Before Weber added lid mounted therms some of us used a wine cork or silicone plug to insert a candy thermometer into one of the holes on the top vent.
So basically we were shutting the vent down by 1/3 or 1/4 depending on the amount of vent holes.

Tim
 
Do what Jeff said! Mark your “One touch” control arm and you will be able to control things much more comfortably.
I saw that on some “ Hot Smoke Barbecue” Site (something like that) and it was really helpful. It’s a very different skill set from using a WSM, it’s really worth looking at. His chicken technique is interesting too!
Kevin, you have started swimming in a fascinating river of gustatory delights, get strong and never forget...
“Success and Failure when cooking end up in the same place.” Be bold, be brave, eat well!

Yes I'd love to be able to mark my ash catcher like that. I saw an Aussie guy recommend doing that in a Youtube video. I would've done it by now...but unfortunately I only have a standard kettle, not the premium, and I can't figure out a good clean way to make any similar markings on this one.

I had my sights on a Original Kettle Premium, and was hoping to score one on sale on Labor Day Weekend. But, everywhere I went I was told that the Weber Kettles don't get marked down ever (unless you can score a display model, which I wasn't too keen on for some reason). So 3 or 4 weeks ago I settled on a base model Original kettle (with a lid from a Premium) that had been used once for $80 from a guy on Craigslist. I've been using it at least a couple days a week but I've definitely been wishing I had that ash catcher every time I clean it out. Now there are 1 or 2 older Original Kettle Premiums on CL, but for $70-80. I could maybe get one of those and use the nicer, newer lid I have with it. But then I'd be out like $150 on an old, pieced-together Franken-kettle Premium, when for about the same price I could've just waited a few more weeks and been able to afford the new Original Kettle Premium in Crimson :maroonkettle: that I really wanted. ARRGHH. Still kicking myself for it. :mad::eek:

Oh yeah, then I saw some guy on Reddit talking about how he bought an Original Kettle Premium on sale for $50 last week. What!?! :confused::mad:

Anyway, thanks for all the input everyone. I think I'll stick with leaving the top vent fully open most of the time and control with the intake. :) :blackkettle:
 
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Get some lightweight chain and a couple of S hooks and put a self tapping screw holding one end to a leg, put an S hook at “Full open” and another at “Half” should work well, maybe more “positive” than marking the pot! Should not be more than a couple of bucks.
 
But then I'd be out like $150 on an old, pieced-together Franken-kettle Premium, when for about the same price I could've just waited a few more weeks and been able to afford the new Original Kettle Premium in Crimson :maroonkettle: that I really wanted. ARRGHH. Still kicking myself for it. :mad::eek:
I'm familiar with that. I thought I'd be saving money when I bought an offset Brinkmann smoker/grill for $100. Turned out to be a complete POS that I spent at least another $200 and dozens of hours of labor on trying to turn it into something worth the trouble of using. I eventually couldn't get past the way too small hot box so the next season I bought the WSM like I should have in the first place.

To a lesser extent I think you're fighting a similar battle with the Weber kettle. It's an excellent grill. Even the base model, that I have also, does a fine job of grilling. But as a smoker it leaves a lot to be desired. I tried to use it that way and had extremely limited success with long cooks. There simply isn't enough room for the charcoal load you need without having heat directly under the meat, particularly if you're smoking something big. So you're stuck reloading charcoal every couple hours. And then, as you've discovered, there's the control of air flow. The vents at the bottom provide only very rough control at the very best. I suspect that's why Weber suggests using the top vent to control the air flow.

If I might suggest, perhaps you should stick with the kettle you have for grilling and start thinking about getting a WSM for smoking. And, please, learn from my mistake. Don't even think about getting some cheap junk for smoking. It will nickel and dime you to death. Better to buy a used good one than a new "bargain" one.
 
I'm familiar with that. I thought I'd be saving money when I bought an offset Brinkmann smoker/grill for $100. Turned out to be a complete POS that I spent at least another $200 and dozens of hours of labor on trying to turn it into something worth the trouble of using. I eventually couldn't get past the way too small hot box so the next season I bought the WSM like I should have in the first place.

To a lesser extent I think you're fighting a similar battle with the Weber kettle. It's an excellent grill. Even the base model, that I have also, does a fine job of grilling. But as a smoker it leaves a lot to be desired. I tried to use it that way and had extremely limited success with long cooks. There simply isn't enough room for the charcoal load you need without having heat directly under the meat, particularly if you're smoking something big. So you're stuck reloading charcoal every couple hours. And then, as you've discovered, there's the control of air flow. The vents at the bottom provide only very rough control at the very best. I suspect that's why Weber suggests using the top vent to control the air flow.

If I might suggest, perhaps you should stick with the kettle you have for grilling and start thinking about getting a WSM for smoking. And, please, learn from my mistake. Don't even think about getting some cheap junk for smoking. It will nickel and dime you to death. Better to buy a used good one than a new "bargain" one.
Yeah I learned from amazingribs.com not to waste time/money/energy/meat on a cheap horizontal offset smoker.

Hmm really? The kettle doesn't do well with long smokes huh? Even with a Slow n Sear?

Guess I'll have to ask the wife for a WSM for Christmas :cool: :wsm22:
 
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Yes I'd love to be able to mark my ash catcher like that. I saw an Aussie guy recommend doing that in a Youtube video. I would've done it by now...but unfortunately I only have a standard kettle, not the premium, and I can't figure out a good clean way to make any similar markings on this one.

So, my first kettle was a basic 18" kettle. When I moved up to the 22", I was sure to purchase the One Touch Gold because I was tired of all the blowing ash. A little while later I modified my 18" kettle with a replacement ash bucket. While I haven't marked my 18" (the 22" and my 18" WSM are much better suited for the long, low & slow cooks), I am very happy with the upgrade.

I say all of that to suggest you look into getting an ash catcher for your kettle. I think the mod cost me like $20-$30 and its super easy since it just snaps into existing slots on the legs. Just a thought
 
So, my first kettle was a basic 18" kettle. When I moved up to the 22", I was sure to purchase the One Touch Gold because I was tired of all the blowing ash. A little while later I modified my 18" kettle with a replacement ash bucket. While I haven't marked my 18" (the 22" and my 18" WSM are much better suited for the long, low & slow cooks), I am very happy with the upgrade.

I say all of that to suggest you look into getting an ash catcher for your kettle. I think the mod cost me like $20-$30 and its super easy since it just snaps into existing slots on the legs. Just a thought

Wait, are you saying that you can add one of the stock Weber ash catchers to a basic kettle? I didn't even know that was an option!
 
Hmm really? The kettle doesn't do well with long smokes huh? Even with a Slow n Sear?
I'm sure it would do much better, but now you've spent another $100 to turn the kettle into a somewhat better smoker that still has issues with controlling air flow. To my mind it's just another version of fixing the offset smoker. You're trying to force an excellent grill into doing something it wasn't designed for. There was something I looked at for the kettle before getting the cheap offset that was similar to the Slow n Sear, though I recall it looking a bit sturdier and having something to help with air flow. Might be remembering it wrong. I decided the air flow was an issue I wasn't going to get past with the kettle.

You can use a screwdriver as a pry bar and kind of pound a nail with the end of the handle, but things go a lot smoother when you have the right tool for the job. If you're only going to barbecue occasionally and in smaller quantities, you can make the Weber kettle work. If you want to do larger quantities or longer cooks, the WSM is the way to go.
 

 

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