Hello, this is my first year with a pellet stove. It has been running fine til now, on stove temp it has never been this hot. I have it on 1 and the flames are high and on the glass and the house is too warm. It will not go to a cooler temp as before. So I turned it to stove temp to see if this would help. Now I am getting a back puffing of flames and a sound and a banging noise. Does anyone have any idea what could be wrong with the stove.