i recently bought and installed a breckwell P2001 fireplace insert pellet stove. the issue i have is soot on the window. the manual says common issues are damper not being open enough,,and pellet auger speed too slow.. i opened the damper 1/2 more and increased the flow of pellets. still i have soot that forms and the top of the windows and seems to flow downward..almost looking like stalagites that form in caves..dripping from the ceiling.. what else can i do to stop the soot from forming on the window??