This standard specifies safety requirements for the design and the installation of hot water-based heating systems with a maximum operating temperature of up to 110 °C.This standard is applicable to hydraulic circuits of either open or sealed water- based heating systems and for the production of hot water for hygienic services, provided with residendial solid fuels burning appliances, as stoves, fireplaces andresidential cookers burning solid fuels not powdered, automatic or automatic- manual, with a forced or a natural circulation of the water , singles or combained with other heat generators, not exceeding a total heat output of 35 kW.