Mine, even when fully closed was still very airy. I unscrewed and re-screwed the center post (that the air flow controller is on) and now it's working more to my liking.
Just didn't know if it was supposed to be very airy even with the control all the way closed.
When mine are closed completely, there's no airflow.
After I find the setting I want, I stick a drip tip o-ring over the threads under the AFC ring to hold the setting. It has been my experience that it usually loosens itself with use, not tighten, so the o-ring fixes the loose AFC for me.
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