Jotul Sebago Bvent , new to us

[DONNY]

I picked this up on Craigslist, cleaned everything out, tested my new gas line, installed pipe to code through our old Duravent thimble in the ceiling via duravents products, installed a new CO monitor in the room, placed logs back in with embers and once air cleared out of the gas line, it fired right up. I would love some advice on 1. the occasional thumping sound it makes and 2. to make sure I am getting an efficient burn with the chute adjustment. 1. Do I just need to clean it again to address the occasional " mild thumping" or are my embers misplaced? 2. Please explain the best blue-to-yellow flame adjustment or is it just as simple as adjusting the yellow until no soot is noticed on the glass? With my shute all the way down I do not see any soot. Thanks in advance... old wood fire Kuma boy