Hello. I am trying to learn how to use the Harman P61-2 pellet stove in my new home. It heats well, but is blowing partially-burned pellets (and plenty of sparks) out of the throat of the burnpot and into the ash box. A few ashes pile up back close to the edge of the fire. This creates a narrow throat where the flames and draft shoot out with a lot of force, enough to eject burning pellets when the feed auger stirs them up. The ashes never get pushed away because the pellets don't stay in long enough. Has anyone else seen this? How can I make the pellets stay until completely burned?