This draft European Standard applies to heating boilers up to a nominal heat output of 500 kW which are designed for the burning of solid fuels only and are operated according to the instructions of the boiler manufacturer. Solid fuels in this standard are: Biogenic fuels: Biomass in natural state in form of: a) A log wood with water content w <= 25 %; b) B1 chipped wood (wood chipped by machine with and without bark, usually up to a maximum length of 15 cm) water content from w 15 % to w 35 %; c) B2 chipped wood as under B1, except w > 35 % moisture; d) C1 compressed wood (pellets without binding agents, made of wood and/or bark particles; permitted are natural binding agents such as molasses, vegetable paraffins and starch); Pellets according to EN 14961-2 (under development); e) C2 compressed wood (briquettes without binding agents, made of wood and/or bark particles; permitted are natural binding agents such as molasses, vegetable paraffins and starch); Briquettes according to EN 14961-3 (under development); f) D sawdust up to w 50 % moisture; g) E non woody biomass such as straws, reeds, kernels and grains. Fossil fuels: a) bituminous coal; b) brown coal; c) coke; d) anthracite. Other solid fuels (e. g. peat): The boilers can be used with natural draught or forced draught. The stoking can be manual or automatic. This standard contains requirements and test methods for safety, combustion quality, operating characteristics and maintenance of heating boilers and covers also all external equipment that influences the safety systems (e. g. backburn safety device, integral fuel hopper). This standard covers only boilers including burners as a unit. A matching of a boiler body with a burner according to EN 15270 is only possible if the whole unit is tested to this standard. The regulations of this standard apply to heating boilers which are to be tested on a boiler test stand by a third party meeting the EN ISO/IEC 17025 requirements. Heating boilers in accordance with this standard are designed for central heating installations where heat carrier is water and whose maximum allowable temperature is 110 °C (safety temperature limiter) and which can operate at a maximum allowable operating pressure of 6 bar. For heating boilers with a built-in or attached water heater (storage or continuous flow heater) this standard only applies to those parts of the water heater which are necessarily subject to the operating conditions of the heating boiler (heating part). The standard does not apply to: central heating boilers and other heating appliances which are also designed for the direct heating of the place of installation; cooking appliances; the design and construction of external fuel storage and transportation devices prior to the safety devices of the boiler; room sealed applications; condensing boilers. The purpose of this standard is to specify the necessary terminology for solid fuel heating boilers, the control and safety related requirements, the design requirement, the technical heating requirements (taking into account the environmental requirements) and testing, as well as the marking requirements.