EN 15316 Calculation Methods for the Generation Sub-system: The Influence of Input Data on the Results

For the calculation of seasonal efficiency and primary energy demand of a heat generation sub-system, a European reference standard (EN 15316-4-1) is available. Two of its methods of calculation are adopted by a specific Italian standard (UNI TS 11300-2). The input data necessary for the application of these methods are often unavailable, and so it is necessary to turn to tabulated data or to data derived from correlations provided by the standard itself. Here we evaluate the effects due to the usage of input data provided by the manufacturers in comparison to those proposed by UNI TS 11300-2. This comparison is carried out for a case study, an apartment provided with a natural gas condensing boiler. The discussion clearly demonstrates the importance of a deep characterization of the heat generator in the calculations of the primary energy consumption.