Solid fuel (wood) burner (closed firebox) – dirty flue

Cause

Build-up of soot/combustion deposits on the inside of the flue – the deposits will build up more quickly where the stove burns slowly for long periods of time during operation, that is, when the damper is closed

Repair

  • have the chimney swept annually
  • let the fire burn vigorously for a period of time each time the stove is lit