Recently while smoking a brisket it seemed like there was more smoke seeping out from my lid than normal. A few years ago I did put lavalock gasket on the top lip of the middle section of my WSM and I don't believe I was getting the smoke seepage I am getting now. Has anyone else had this problem? Does anyone know what the life expectancy is of the lavalock gasket? I am likely going to redo the gasket but would love to know others experiences. Thanks, Joe.
WSM - Lid Gasket Leaking
- Thread starter JoeCPA
- Start date
I keep the top vent only about 20% open, maybe even a bit less. I have the Flameboss 400 which supplies air as needed to the coals. Initially a fair amount of smoke comes out of the top vent when the coals and hard wood first ignite. Do you think there is too much pressure from not allowing the top vent to be open more?
Bob Bass
TVWBB Gold Member
When heated, molecules of air become more active requiring greater space. Heated air is less dense than unheated air, so it rises. If there is not enough space for that heated air to escape through the top vent, it will try to escape through the top to middle section "seal".
While I do not use a Flameboss, I have always had my top vent 100% open. My current ATC is a Thermoworks Signals/Billows which replaced my Rock's BBQ Stoker used since 2011.
Opening your top vent some additional amount may or may not work in you particular case. But somehow, I think it is worth a try ....
Thanks Bob. I will open the top vent more and see if this remedies the problem. I appreciate your time spent in providing your advice. Thanks again, Joe
Jim C in Denver
TVWBB All-Star
Joe -- I would note that the instructions to my Billows say to keep the top vent mostly closed -- 1/8th open to start. Which is totally different than the standard instructions for non-ATC use -- top always 100% open.
You'll get more smoke out of the vent vs rim if you open up the vent. But just be aware that, with an ATC, a more open top vent may change how the cooker operates.
You'll get more smoke out of the vent vs rim if you open up the vent. But just be aware that, with an ATC, a more open top vent may change how the cooker operates.
Thanks Jim. My gut feeling is that it may cause the charcoal to be used up a bit quicker because of the blower needing to generate more heat due to the greater escaping of heat caused by the vent being opened more. I am also still thinking of replacing the heat seal on the rim and seeing how that affects the seeping of smoke.
Jim C in Denver
TVWBB All-Star
Not a scientist, but I think that's how it works with an ATC.
As compared to manual operation, the volume of airflow is more limited and controlled. Which, I guess, makes it easier for the puffer to make small adjustments around the set temp. So you close all but one bottom intake vent and keep the top outflow vent 80+% closed.
A new gasket on the rim should make the lid less leaky. TBD, however, if a more/less leaky lid would make any cooking difference.
Tightening up leaky spots would mean, I guess, that the cooker would be more sealed and efficient. So you'd burn less fuel to maintain the target temp (good I guess), and would have less airflow through the cooker. No idea if that lower flow is good, bad or neutral on how the cook turns out.
As compared to manual operation, the volume of airflow is more limited and controlled. Which, I guess, makes it easier for the puffer to make small adjustments around the set temp. So you close all but one bottom intake vent and keep the top outflow vent 80+% closed.
A new gasket on the rim should make the lid less leaky. TBD, however, if a more/less leaky lid would make any cooking difference.
Tightening up leaky spots would mean, I guess, that the cooker would be more sealed and efficient. So you'd burn less fuel to maintain the target temp (good I guess), and would have less airflow through the cooker. No idea if that lower flow is good, bad or neutral on how the cook turns out.
Thanks Jim for your feedback - it is much appreciated.
Bob I have had my WSM for about 3 years now, so I am still a total newbie to smoking and appreciate very much the advice from experiencef individuals like yourself and Jim. If I may ask, what does ATC and PID stand for?
Also, I just got back from visiting friends in Texas and had some of the best darn brisket I have ever had. It has really motivated me to work on my brisket - though it comes out very tender I still have a ways to go.
Bob Bass
TVWBB Gold Member
Hi Joe,
ATC is Automatic Temperature Control. At the heart of the ATC is a PID controller. The P is for Proportional, the I for Integral and the D for Derivative. These 3 functions form the adjustable 'control settings' that determine how the PID controller responds in an application. PID controllers are found often in our current world. Like in your car's cruise control.
The systems I worked with were manufactured by the likes of Leeds & Northrup, Honeywell, Foxboro amongst others. Some applications controlled temperature in large rotary kilns, some controlled liquid flow rates, while others controlled how much rock is feed via pan and belt feeders to large rock crushers. Thankfully most all PID controller moved over to software based systems, as the pneumatic and electronic systems had their own teething issues.
ATC is Automatic Temperature Control. At the heart of the ATC is a PID controller. The P is for Proportional, the I for Integral and the D for Derivative. These 3 functions form the adjustable 'control settings' that determine how the PID controller responds in an application. PID controllers are found often in our current world. Like in your car's cruise control.
The systems I worked with were manufactured by the likes of Leeds & Northrup, Honeywell, Foxboro amongst others. Some applications controlled temperature in large rotary kilns, some controlled liquid flow rates, while others controlled how much rock is feed via pan and belt feeders to large rock crushers. Thankfully most all PID controller moved over to software based systems, as the pneumatic and electronic systems had their own teething issues.
Jim C in Denver
TVWBB All-Star
Bob -- I've looked for the definitive answer on this question. Folks, including Harry, are all over the place from what I can find.
Flameboss, DigiQ and Billows all say top vent almost closed -- for better temp control I guess.
I've seen where Harry says that he goes with the top 100% open with or without an ATC. But Harry's site also says this:
"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."
Maybe the advice you got from Harry (top always open) was more about good smoke and airflow? And not so much about temp control?
Or maybe it doesn't actually matter that much?
Bob Bass
TVWBB Gold Member
Jim...
Could it be because those ATCs mentioned did NOT have an internal airflow "flapper" in the fan housing that limits or stops free air flow ? On the Rock's BBQ Stoker fan, there was a vane in the fan's output that opened only when the fan was on. It closes when the fan was off, so as to stop any free air flowing to the BBQ's heat source. If so, could it be that closing down the top vent is recommended because the ATC manufacturer didn't design their product to only deliver air when needed ?
Could it be because those ATCs mentioned did NOT have an internal airflow "flapper" in the fan housing that limits or stops free air flow ? On the Rock's BBQ Stoker fan, there was a vane in the fan's output that opened only when the fan was on. It closes when the fan was off, so as to stop any free air flowing to the BBQ's heat source. If so, could it be that closing down the top vent is recommended because the ATC manufacturer didn't design their product to only deliver air when needed ?
Hi Bob, the Flameboss works by having all of the bottom vents closed except the one vent that it is connected to, and that connection is via a plate that essentially prevents air from entering the charcoal area by other than that generated by the blower. So essentially this unit is designed, and when installed properly, to allow air to be delivered only by the ATC unit as it determine the air to be needed for maintaining temperature. I have no doubt that there is some air free flow that probably still goes on, but I have to believe it is very insignificant and inconsequential to the fueling of the charcoal - especially since when my smoke is done I close the top vent entirely in order to smother and save the unused charcoal, for use another day.
To Bob's comments regarding the use of the top vent to control a draft which essentially feeds the charcoal and thereby controls the temperature, I find this interesting. Before I got my WSM I would use my weber kettle and the minion method to smoke my brisket. I never touched the bottom vents and always kept them wide open. It was the top vent that I manipulated to control my temperature, and which required more regular monitoring - which I no longer have to do with my WSM due to the ATC attached to it. Keep of cool to find out I was doing it right back then.
To Bob's comments regarding the use of the top vent to control a draft which essentially feeds the charcoal and thereby controls the temperature, I find this interesting. Before I got my WSM I would use my weber kettle and the minion method to smoke my brisket. I never touched the bottom vents and always kept them wide open. It was the top vent that I manipulated to control my temperature, and which required more regular monitoring - which I no longer have to do with my WSM due to the ATC attached to it. Keep of cool to find out I was doing it right back then.
Thanks all for my continued education on using my WSM and your feedback. This bulletin board is awesome and it is great to be able to reach out to all you experienced smokers and be fortunate to receive your responses. I will post an update on my smoke seepage issue when I do my next brisket, which will be soon.
Jim C in Denver
TVWBB All-Star
Maybe. But I'm coming around to the conclusion it probably does not much matter. Since the bottom is mostly sealed (except for the fan input).
So if you leave the top mostly closed (as the manufacturers instruct), you will retain more heat, the fan will puff less, and the cooker will be more efficient.
If you open the top vent (same as opening a window in your house) you will lose some heat. So the fan will puff more, charcoal will burn more, and you'll have more flow going through the cooker.
Who knows if more flow or lesser flow results in better product. Feels like that gets you into the whole creosote good/bad smoke discussion.
Also seems like on a kettle, WSM and many other cookers, you can primarily control the airflow and temp from either the top or the bottom.
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I always treated the bottom vents for gross adjustments and the top for fine adjustments. When I first first got my WSM a few years ago I was more concerned about holding a specific temperature but now I'm not so picky. If it stays within about 15 degrees of my desired temperature of my set temperature I'm good with that. I usually aim for about 250F. I now keep the top vent 100% open regardless but I'm not using a ATC.
I keep my top vent open 100% always. You’re gonna get the smoke flavor regardless.