This is usually caused by poor draft or draw. The chimney system does not pull hard enough to move the exhaust fumes quickly through the secondary burn off system. Volatile flue gases then ignite inside the main combustion zone (the fire) and make small puffs of smoke. Poor draw could be caused by one or a combination of one of the following:

  • Chimney system (connector pipe and chimney) not to the minimum height - usually 16’ from the stovetop.
  • Dilution of the draft (air pulled in from a source other than through the firebox) in the chimney caused by a loose or missing clean out; a loose flue collar; loose connector pipe joint or a crack in the masonry chimney if used.
  • Blockage or restriction of the exhaust path, caused by build up of ash in the secondary combustion zone; blockage in the catalyst if present; clogged rain cap or blockage in the chimney.
  • Burning unseasoned wood.