This master thesis deals with the construction and commission of a heat pump testing station. This testing station is made for water/water and brine/water heat pumps. Through the concept of a closed cycle during the heat pump testing, the heat pump generates its own test conditions. This is possible through a heat recovery from the heat sink into the heat source. To keep the test temperatures constant, the regulation scheme is programed by means of fuzzy logic. For a complete record of data during the test procedure 14 temperature sensors, four pressure sensors and three flow sensors are installed in the testing station. For testing a heat pump ratios are required. One of the most important is the coefficient of performance (COP). It is calculated from the generated heat power of the heat pump, divided by the required electrical power. In this thesis, the coefficient of performance is used for evaluating the functionality of the heat pump testing station. The European Norm EN 14511: 2013 regulates the testing of heat pumps. It defines four different test temperature levels. Starting from 10 C in the heat source an increase of the temperature up to 65 C is required. The part of the results includes two main topics. On the one hand, the verification of the compliance from the maximum permissable deviation from the desired temperature according to the European Norm. And on the other hand the results of the testing station validation, these are compared to the manufacturer's data, and a computer simulation with the IPSEpro program. The static calculations in IPSEpro are carried out using data from the audit records. With the programed fuzzy-regulation it is possible, for the executed tests within this thesis, to comply with the required limits according to the European Norm. In the second case, comparing the test results with the manufacturer's data and the IPSEpro simulation results are almost identical. This indicates the correct operation of the testing station.