Each size is available in standard form (GBDF series) for atmospheric boilers and water heaters of circa 75% efficiency. Enhanced corrosion resistance versions (SSDF series) with stainless steel fan cases are also available for installation where regulations or the specification calls for stainless steel duting, and, when higher efficiency boilers such as modular designs are likely to produce condensation. Condensation should not be allowed to collect in the fan casing.
Updated in October 2005 a new range of dilution fans including Stainless Steel versions for enhanced corrosion resistance, which allow flexible sitting of gas boilers rated between 80 kW and 650 kW input. Upgraded to include a pressure switch fail safe system and an easy to connect mains flying lead with snap-in plug and socket, the Airflow range of flue dilution fans is available in 5 sizes to satisfy the dilution needs of industrial and commercial boilers.