VC WinterWarm 2080 Fireplace insert... Recently I've noticed build up on the front glass left side near latch, also it appears the fire wants to start and burn on the right side of the firebox and then works it way over to the whole log? I replaced the gaskets on both the door and glass but it did not change? What am I dealing with? Could it be the air flow lever? as that is on the left side towards front of stove?