Seems the common system of burning in the 30 is to pull coals to the front and load n/s. That has proved the best burn for me. Problem may be happening with blockage of the air though. The lower channel has ports just above the bricks. They are always blocked with ash. The ash is getting pushed into the channel in the process of pulling coals forward. I blow air from a vac into the primary inlet to try and clean the ash out every few days. Can't tell if that is working. Anyone else giving attention the those ports?