Abstract
Currently, 59% of the installed heating appliances in EU28 is rated as C or D class, meaning a seasonal efficiency lower than 82%. In addition, the actual replacement rate is only 4%/year. With the HARP project, we aim at raising consumers awareness to the opportunities underlying the planned replacement of their old and inefficient heating appliance. For this purpose, we developed a labelling methodology for old appliances that can be applied by a common or by a professional user in its “simplified” or “detailed” version. The activity started from identifying the state-of-the-art regarding existing and envisaged labelling schemes for old appliances in Europe, in order to develop an approach that can be used in all countries. The validation process included about 4600 space heating boilers built from 1972 to 2019 and has facilitated a simplification of the inputs that a common user should introduce in the tool for the calculation of the seasonal efficiency. The agreement between the “simplified” and “detailed” calculations is 3.3%. Three models have been tested in laboratory confirming the reliability of these results.