Why does the boiler smoke?

When the airflow to the boiler is greater than the chimney draught, the boiler will smoke. The reason may be: – wrong chimney (leaky, with forges to other flues) – too small cross section or height of the chimney – external chimney not insulated – additional device connected to the same flue – dirty chimney or boiler – lack of chimney connection installed – fumes should go up a slight slant already after leaving the boiler – too deep connection to the chimney – ventilation grate on the ceiling with too large size, which can cause draught in the wrong direction.
Main reasons:
– cross section of the chimney is too small for the boiler design
– damaged chimney (with holes – causing the draughting of “left” air)
– too many bends, knees at the installation of the boiler – chimney line (reduces the possibility of chimney haul)
– contaminated chimney (too much soot – clean the chimney and then burn the boiler at higher temperatures of 65-75 degrees of Celsius)
– the sealing cold worn as a result of the boiler operation – adjust the pressure on hinges, and if the problem persists – replace the cord.