WSM Top Vent Open 100%?

[bakerman]

I had the devil of a time last weekend getting my WSM to behave. Most of my problems were due to my newbie ( to charcoal ) attempts at maintaining a perfect temp.

So after I finished the cook I started thinking about the top vent as a controller, in lieu of just using the bottom vents. I know most of the advice is "leave it open", but I'm thinking this might help me some. I know I created some problems myself with fiddling, but I am learning a lot about this way of smoking food.
I realized that my temp probe was probably in a "hot spot" after the cook, so next time it will go in the middle under side of the grate. My lump charcoal/ briquette minion method is one of the main contributors of my variant spikes too. Put too much hot coals in the Minion method at the start. Thing took off like a rocket ship.
I put water in the water bowl, and that helped some. Next time I will start with water in, instead of adding it later. I will also use less of a starter chimney. I went full this last time. Of course opening the WSM periodically did not help, so I blame myself for that.

Anyway after learning all of this, I was wondering if any one here uses the top vent for better temp management. My thoughts are to get the WSM up to 200 and start closing off the bottom vents, 2 completely and one 3/4 closed. Then using the top vent only for temp adjustment. I know this is only my fourth cook on this and I have a long way to go yet, but I am not going to get any attachments, fans etc. just yet. I want to find out if I can manage this thing as is.

Thanks in advance

 

[yankee2bbq]

I don’t use the top vent on my WSM 22. I always keep mine fully open.
Sounds like you started with too many hot coals.
I pour a whole bag of Royal Oak briquettes in the bottom of my WSM, take out 10 briquettes from the center, place those ten in my upside down chimney starter, light those ten. When those ten ash over place in the center of the briquettes of the in the smoker.
Put the WSM together, bottom vents wide open. When you get around 25 degrees of your desired temperature, start closing the bottom vents halfway close.
It may take up to 90 minutes for your WSM to preheat. Patience my friend. Also, I do not use water in my water pan. I cover the pan in foil. Like a lid.
Hope this helps.

 

[browneyesvictim]

You can. But you will fine you don't need to. You will get it figured out. By what you are describing it sounds like you have a good handle on what you need to do. Yes, patience.

 

[bakerman]

Appreciate the feedback. Yes I was impatient, however I did wait for a full hour before putting my meat on. But as soon as I did that the temps took off, 350 and climbing! I had to add water etc. But I know now. Don't open it up for too long. After about 30 minutes above 300 it crawled back down to 275. But I could not get it to stabilize.

 

[BrianGSDTexoma]

You are on your way. All grills and smokers have a learning curve. Don't get to obsessed with temps. Any where in the ball park will work.

 

[sandyut]

I used a WSM for years. There is a learning curve for sure and patience is needed. But - I always had the top vent wide open and controlled the temps with the bottom vents. For a minion start, you don't need many coals. I didnt catch the size of you WSM, but that is kinda the determining thing on that. I used the water bowl for a while till i dialed in my processes, then i just covered it in foil empty. if you want to make this REALLY easy - check out a controller from BBQ Guru I used a PartyQ and loved it. It might be discontinued. But these work very well and conserve coals.

 

[Colin1230]

With experience comes confidence and you are well on your way to getting your WSM figured out. Normally the top vent is 100% open but I have closed it to approx. 50% in windy conditions. Brian's advice above is spot on about temperature. If it is anywhere between 225* and 275* its good.

 

[bakerman]

I used a WSM for years. There is a learning curve for sure and patience is needed. But - I always had the top vent wide open and controlled the temps with the bottom vents. For a minion start, you don't need many coals. I didnt catch the size of you WSM, but that is kinda the determining thing on that. I used the water bowl for a while till i dialed in my processes, then i just covered it in foil empty. if you want to make this REALLY easy - check out a controller from BBQ Guru I used a PartyQ and loved it. It might be discontinued. But these work very well and conserve coals.

Mine is a 22.5 wsm

 

[bakerman]

With experience comes confidence and you are well on your way to getting your WSM figured out. Normally the top vent is 100% open but I have closed it to approx. 50% in windy conditions. Brian's advice above is spot on about temperature. If it is anywhere between 225* and 275* its good.

Yeah it plays havoc on my OCD.

 

[SmokinAl]

I have had a WSM/Guru setup for a bunch of years, I always keep the top vent open 100%. Before I had the Guru I would usually close 2 bottom vents, leave one open about 1/4 of the way & leave the top vent open 100%. It would usually settle in somewhere between 225-250.
Al

 

[noboundaries]

Top vent full open. No water in the pan.

You can slightly close the top vent to choke the fire but it won't help your learning curve and can introduce taste issues you won't enjoy.

Heat - Air - Fuel is the fire triangle. The irregular surface of lump charcoal allows ANY increase in air to stoke the fire. I only used lump when I wanted a hot fire. If you placed your wood chunks on the top of charcoal, they can ignite whenever more air is added. Bury them instead where they can preheat and carbonize cleanly.

Since you're new to the WSM, chances are good you're following the HORRIBLE starting directions of the manual. They recommend WAAAY too many hot charcoals to start the fire. I use no more than 8-10 hot charcoals to start a low n slow fire.

Last recommendation is to set your bottom vents at their final position when starting the fire, not full open like the manual recommends. 1/16"-1/8" on each lower vent will give you a 225-250F fire. It takes 2+ hours to reach temp, but you don't have to wait that long. I'll load my meat when I see clean smoke even if the chamber temp is only 190F. The fire is tracking toward 225-250F.

And remember, cold meat has ZERO impact on the fire. The chamber temp will drop because cold meat is absorbing available heat but the fire is just chugging along.

Keep your chamber probe at least a couple of inches away from the meat and not directly under the top vent. The first will give you too low a reading; the latter too hot.

Be patient starting the fire and you'll find hours and hours of steady WSM temps without using the massive heat sink of water in the water pan.

 

[bakerman]

Great info noboundries. I did use too much charcoal in the chimney, and my probe was on the outer edge of the lower grate. So the fluctuations are understandable. The temp spike when I put the meat on was due to the air that was feeding the flame. Also I did not bury the wood chunks. I lay them on top, and they were gone pretty quick after I started.

I intend on my next cook to rectify all my errors, and to be more patient. I am my own worst enemy at times. My question about the top vent may not fit with the way you experienced people cook. I will consider that next time.

I know that the water pan question goes round and round, I will just have to keep a record on that and try different methods. I did go waterless on my second cook (chicken wings) , but that was hot and fast so I wasn't too concerned about low and slow.

The last recommendation is interesting. I will give that a try too. At the rate I'm going I should have it pretty close in a few years LOL.

 

[Hamdrew]

I do, but as others said might not recommend it yet. You can easily get white thick smoke from smoldering wood/charcoal.

This is a new WSM, correct? They always run hot- after a handful or two of cooks, the same bottom vent settings that were 325*F+ might run at 275*F or even less. Until then, there's a few things you can do to help better control it:

1. Use the waterpan, adding a liter of water every 1-2hrs
2. Only use one intake vent ever barely cracked. The farther any lit coals are from that intake, the lower temp you will have.
3. Don't use the minion method yet, only using small amounts of coals. If not using the water pan, you can either toss in more lit coals as needed, or use tongs to put in the coals
4. Only smoke chicken drums/thighs/leg quarters til the WSM is seasoned enough

 

[bakerman]

Thanks Hamdrew,
Yes this is a new WSM. I've smoked (so far), BBQ Meatloaf, Chicken Wings (twice) and the last run was 4 slabs of spare ribs. Even with all the issues I have had or created the food always turned out great or at least pretty good.

I have a couple of Tri tip in the freezer that have been crying out for some heat. Probably do some chicken thighs next.

 

[JWFokker]

It will get better/easier to control temps as the cooker gets caked with creosote. Any small leaks will get sealed and the vents will give a better response.

In general though, you can get by starting with fewer hot coals if you're willing to wait. Better than too many and trying to choke down the fire.

 

[SlowmotionQue]

The top vent in a WSM has the largest influence on your temperatures. Harry Soo explains this below and one can google it to determine where he states it, as I don't believe that it is permissible to post a link to a rival forum or page.

But I have found it to be a fact.

For more information on the influence of your top vent, or exhaust vent, Harry Soo offers the following:

"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"

 

[bakerman]

SloMo that is what I was talking about! Thanks for the information.

 

[noboundaries]

The key to Harry's POV is his following statement:

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.

New WSM pitmasters must learn lower vent input control BEFORE they start learning how to make exhaust tweaks.

When I started learning to smoke on a Weber Kettle, I left my bottom vents full open and controlled temps with my top vent. Why? Heck, I was an engineer so I understood draft. Result? I was constantly chasing steady temps.

Graduated to the WSM and switched to bottom vent control only, top full open. After a learning curve of charcoals, vent settings, and wood loading techniques, I found hours and hours of steady temps. I used the same bottom vent settings, top full open, on my Kettle and bingo, no more chasing temps.

After 6 months I added a Guru to the WSM because I had an company awards card I had to use. It was a nice addition that is now gathering dust once parts started failing. Before that though, I began using it on overnight smokes as an insurance policy against falling temps (ambient temp drops, dew points, wind, etc can all impart chamber temp changes).

Have I used the top vent to control temps? Yes, after TBS is WELL established. A minor change (1/16" to 1/8") to the top vent will have an impact on climbing temps within minutes. BUT, you may find yourself chasing temps an hour later if too large a change is made. Been there. Making tiny adjustments to the bottom vents give better steady results.

There's no shortcut to experience. There's no perfect technique. There's only heat, smoke, time, and patience.

 

[bakerman]

noboundries,
I understand what you are sayin'. Only reason I started this thread was to find out more info on using the top vent. I am still a greenhorn to WSM technique, so I will heed your advise. Looks like I need a few more cooks to get this settled in.
I'm planning on some smoked chicken thighs for this weekend. Running hot and fast , so not much of a low and slow cook. That will occur in two more weeks. Probably smoke a shoulder or butt to see if I can run for several hours at a stable (+/- 15 degrees) temp. I will use the bottom vents for temp control to start. Use less hot coals and put my temp probe in a better location, instead of close to the side. All the information from everyone helps.
This is the place for help that is for certain.

 

[SlowmotionQue]

As far as the efficacy of using the top vent to control temperatures, the following graphs of a few of my cooks using the top vent and a Fireboard 2 Drive controller, BBQ Guru fans in a 22in WSM with the top vent 2/3rds closed, and running a full oversized water pan, should offer some insight.

The dips are where I opened the lid. The "up" step up in the first graph is where I jacked up the temp from 225°F-250°F.

In my WSM, I set my top vent where I want it and leave it there. About 2/3rds closed in all three of the graphs below. These results are typical for me in my 22in WSM.

I learned this from the instructions that the Thermoworks Bellows owners use ( I have a Fireboard 2 Drive and a BBQ Guru CyberQ and this near shutdown top vent technique works with both of them), where Thermoworks recommends shutting down the top vent a significant amount.

This ties in to the recommendations by Harry Soo regarding temperature control.

Worthy of mention, as stated before I am a BBQ Guru Cyber Q owner as well. And I would battle high temperatures running that setup according to the instructions which were to run the top vent wide open.

It wasn't until someone pointed out to me the Thermoworks Bellows instructions, whereby the recommendation is to shut the top vent down somewhere around halfway .

I started doing that with my BBQ Guru CyberQ and never had another problem with temperatures being overshot using it again.

I then graduated to the Fireboard 2 Drive as my CyberQ was becoming outdated. And with the Fireboard 2 Drive, still I shut down the top vent to about 1/2 to 2/3rds closed.

The results are in those graphs.

And no, I don't get stale or white smoke, or dirty smoke, but I get thin blue smoke with the top vent shut down to the level that I'm describing.

Were I getting dirty smoke, I would not use this technique.