The Materials

Each Metal Chimney must present and guarantee over time the maximum tightness for the safety of those who use it and the buildings it serves; particular attention is therefore required by the problem of acid condensation, both in gaseous combustion systems and in wood such as stoves and fireplaces.

CANNA srl uses the best materials, such as INOX AISI 304 BA and AISI 316 L BA, against corrosion, in particular 316 due to the presence of 3% molybdenum; the polished finish of BA reduces the internal roughness of the wall and therefore facilitates the draft, hindering soot deposits, and ultimately, reducing maintenance costs and intervention times.

However, the most deleterious factor for the flue is acid condensation (pH 3.5-3.6), the presence of which causes corrosion; therefore it remains necessary to limit it quantitatively in its formation also with the choice of the appropriate thickness, in addition to the choice of an adequate thermal insulation.

The thickness of the material used is 5/10 or 6/10 mm (for special applications greater thicknesses are used); a choice of balance between mechanical strength and resistance to corrosion,which allows the achievement of thermal equilibrium in less time and therefore the formation of less condensation, heating the wall faster which thus quickly leaves the dew zone by first exceeding the condensation temperature.

Times that are even lower if the flue has adequate insulation that hinders heat loss byimproving the draft, the greater the hotter the fumes and therefore the greater the difference in temperature (therefore density) with the surrounding outdoor air.