I had one 2 nights ago on my 340. Similar circumstances - making burgers, cranked up to 500, and went inside. I was surprised how much smoke I was getting at 500 and when I opened the lid, I saw why. Threw some baking soda on it and pulled the plug to stop the fan. The grill seemed to survive unscathed.
I too was lazy and had not cleaned the drip pan. The previous cook was smoking a pork belly for bacon, so lots of drippings on the foil lined pan. I had done 80/20 burgers before with no issues. Not sure I'll do it again.
I too was lazy and had not cleaned the drip pan. The previous cook was smoking a pork belly for bacon, so lots of drippings on the foil lined pan. I had done 80/20 burgers before with no issues. Not sure I'll do it again.