ÖNORM EN 621

This European Standard specifies the requirements and test methods for the safety and efficiency of non-domestic gas-fired air heaters not exceeding a net heat input of 300 kW with (an) atmospheric burner(s) and without a fan to assist the transportation of combustion air andlor flue gases, hereafter referred to as "appliances". This European Standard applies to Type B11, C11 and C31, appliances intended for use in other than single unit residential dwellings. Provision of the heated air may be by means of ducting or may be directly into the heated space. This standard does not apply to: appliances intended for use in a single unit residential dwelling; appliances of the condensing type; appliances for outdoor installation; dual purpose air conditioning appliances (heating and cooling); appliances where the air is heated by an intermediate fluid; appliances with forced draught burners; appliances fitted with a manual or automatic means of adjusting the combustion air supply or the combustion products evacuation (including flue dampers); portable or transportable forced convection appliances; appliances having multiple heating units with a single draught diverter; appliances fitted with more than one flue outlet. This European Standard is applicable to appliances which are intended to be type tested. NOTE: Requirements for appliances which are not type tested would need to be subject to further consideration.