UNE-EN 303-6:2021

This European Standard is composed of two parts.The first part supplements EN 303-1, EN 303-2, EN 303-4 and EN 304 hereafter called boiler standards. It specifies the supplementary requirements and tests for the construction, safety, rational use of energy, fitness for purpose, classification and marking related to the domestic hot water operation of oil-fired water heaters and combination boilers.The domestic hot water is produced on either the instantaneous or storage principle. The domestic hot water production is integrated or coupled, the whole being marketed as a single unit.The second part covers the energy performance of domestic hot water production of the appliances covered by the first part.This second part sets out a method for assessing the energy performance of the appliances. It defines a number of daily tapping cycles for each domestic hot water use such as kitchen, shower, bath and a combination of these, together with corresponding test procedures, enabling the energy performances of combination boilers and water heaters to be compared and matched to the needs of the user.The heat output of the appliances covered by this standard does not exceed 400 kW.In the case of combination boilers, with or without storage tank, domestic hot water production is integrated or coupled, the whole being marketed as a single unit.This standard only covers type testing.