The heat source system is equipped with 2 boreholes with a total length of 160 m. The heat pump contains an integrated DHW storage. A circulation pump is used for DHW supply, in addition a buffer storage is installed in the heating circuit. Furthermore a passive cooling module is installed in the system. Due to underfloor heating and low inlet temperatures, there are good preconditions for the heat pump system.   

Efficiency of 3.9 in 2010 reflected the average of this type of system. Good efficiency values can be explained by low inlet temperatures in the heating circuit and high temperatures in the brine circuit in winter. The brine pump's 12 % share of the total electrical energy demand is above the average of 6 % and thus influences the SPF negatively. In 2010 the share of DHW amounted to 11 % and this lied below the average of 18 % and is responsible for good efficiency values as a low temperature level for the heating circuit was needed.

  * in accordance with EN 14511