ÖNORM EN 777-3

This European Standard specifies the requirements and test methods for the construction, safety, classification and marking of non-domestic gas-fired overhead radiant tube heaters incorporated into a multi-burner system (referred to in the body of the text as the system) with each burner unit under the control of an automatic burner control system. This standard is applicable to type B22x and type B23x systems (see 4.3) intended for use in other than domestic dwellings, in which the supply of combustion air and/or the evacuation of the products of combustion is achieved by mechanical means. This standard is not applicable to: systems designed for use in domestic dwellings; outdoor systems; systems in which the heat input of an individual burner unit exceeds 120 kW (based on the net calorific value of the appropriate reference test gas); systems having a draught diverter incorporated between the exhaust fan and the flue duct; systems having fully pre-mixed gas and air burners in which: either the gas and all the combustion air are brought together just before the level of the combustion zone; or the pre-mixing of the gas and all combustion air is carried out in a part of the burner upstream of the combustion zone. This European Standard is applicable to systems which are intended to be type tested. Requirements for systems which are not intended to be type tested would need to be subject to further consideration. Requirements concerning the rational use of energy have not been included in this European Standard.