SEASONAL PERFORMANCE AND TEST OF MULTI-FUNCTION HEAT PUMP UNITS
The energy need for space heating is decreasing significantly in modern highlyinsulated dwellings. Thus, in the recent years ventilation compact units with heat pump have been developed for low energy houses, which combine the functions space heating (SH), domestic hot water (DHW) and ventilation in one unit. To assess the overall performance, the seasonal performance factor (SPF) has to be calculated by a standardised method. In the draft standard (prEN 15316-4.2) a temperature class based calculation method (bin method) for heat pump systems with SH and DHW operation has been introduced to calculate the SPF and respectively the electricity input. This standard is to support the implementation of the Energy Performance of Buildings Directive (EPBD 2003). The method has now been extended to multi-function units with ventilation, heat recovery and optional solar collector and ground-to-air heat exchanger. The results of the calculation method have been validated with measurements of two pilot plants. Furthermore, an exergy analysis for heat pump compact units provided a method to compare system layouts by showing the influence of the different loss mechanisms on a uniform basis.