I have a 120,000 btu hardy wood boiler...I bought it used and am not understanding why it only ever seems to have a small fire and not an inferno... it has a sealed blower that feeds thru the ash tray which seems to blow great. I can feel tons of air flow out the chimney when blowing w no fire in the box..I'm using seasoned split wood..have a clean ash tray.. but it only seems to make a fire that you would want to roast marshmallows on. What am I doing wrong?