You can fill it clear to the top of the fire ring if you want, but you shouldn't have to. I have opened the vents on mine many times after a messy low and slow cook to do a clean burn with less than half a fire box full and it still buries the thermometer.
Are you leaving the lid open to get a good fire going before closing it up? Have you checked calibration of your thermometer in boiling water? What are you lighting with? This is bugging the crap out of me.
Mike
Know fat, know flavor. No fat, no flavor.
I tried going vegan, but then realized it was a big missed steak.
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