This European Standard specifies the requirements and test methods for the safety and efficiency of gas fired air heaters with or without a fan to assist the transportation of combustion air and/or flue gases, hereafter referred to as appliances . This European Standard applies to Type A2, A3, B11, B11AS, B11BS, B12, B12AS, B12BS, B13, B13AS, B13BS, B14, B14AS, B14BS, B22, B23, B41, B41AS, B41BS, B42, B42AS, B42BS, B43, B43AS, B43BS, B44, B44AS, B44BS, B52, B53, C11, C12, C13, C21, C31, C32, C33, C41, C62 and C63 appliances with an input not exceeding 300 kW (net CV basis), intended for use in single unit residential dwellings and in other than single unit residential units. Provision of the heated air may be by means of ducting. This European Standard does not apply to: a) dual purpose air conditioning appliances (heating and cooling); b) appliances where the air is heated by an intermediate fluid; c) portable or transportable forced convection appliances; d) domestic appliances for outdoor installation; e) appliances fitted with manual or automatic means of adjusting the combustion products evacuation by means of flue dampers; f) appliances having multiple heating units with a single draught diverter; g) appliances fitted with more than one flue outlet; h) appliances fitted with gas boosters; i) domestic appliances of type C22, C23, C42, C43, C52 and C53; j) C21 and C41 appliances for 3rd family gases; NOTE For C41 appliances, see all requirements and test methods that are valid for C21 appliances, unless otherwise stated. This European Standard is applicable to appliances which are intended to be type tested. It also includes requirements concerning the evaluation of conformity, including factory production control, but these requirements only apply to POCEDs and their associated terminals.