This European Standard gives a review of influencing factors on the corrosion likelihood of metallic components (pipes, tanks, vessels, heat exchangers, pumps etc.) in water circulation systems in buildings.The water circulation systems considered are: heating systems (up to 110 °C service water temperature); cooling and chilling systems;which are filled with potable water or water of similar composition according to the Directive 98/83/EC.NOTE 1 Sanitary hot water systems with a re-circulation loop are not considered in this European Standard as they are not really closed system, because the water is continually renewed. The corrosion likelihood of these s