Trouble Burning Nut Coal in Mark III

I didn't read all the posts in this thread but I'll put my 2 cents in on the OP's question. I have BaroDamper and a MPD. Use both in harmony. I always pile the coal up so it just about falls out before shutting door for the day or night. MPD is shut. Baro is set for intense heat. It will open with the draft increase of a hot fire keeping it at bay somewhat. With that kind of opening and heat output frequent tending is needed.
1 1/4 turns is alot with Nut and cold temps outside. The glass on the door being loose I believe is done on purpose from Harman. It allows air to mix with the Natural gas produced by the coals and burns it. Thus Blue flames.
Love this Harmon..going on 4 seasons now. I have it in the basement and never has a alarm go off unless I didn't open the MPD when serviceing it. I have a outside Stainless chimney and temps here in Northern NH get to 25 below .

I'm running mine at 2 turns out, and it's only in the 20's. On real cold days I'll run 2.5 turns out. Goes to show the difference draft plays in burn times & damper settings.