The Cartographic and Geological Institute of Catalonia (ICGC) aims to analyze the operation of a ground source heat pump (GSHP) facility, which pertains to an office building located in the Catalan territory and inaugurated in 2012. This installation serves as the unique source for heating, cooling and domestic hot water production. The facility has a monitoring system that records the time-evolution of the main operation and performance parameters. This study was carried out within the work frame of a larger project from the ICGC, which is called “Low temperature geothermal atlas”. The main objectives of this work are: a) To build an empirical model able to reproduce the operation and performance of the installation through the use of Ground Loop Design software (v2016), in parallel with a rigorous determination of the actual thermal load of the building. b) To analyze the results of the model and compare them with the actual data gathered by the monitoring system, to evaluate the actual performance of the installation and to identify possible strategies to improve its performance. Both objectives converge to determine the necessary actions for an optimum performance of the installation. It will allow us to quantify the potential of the facility to cover additional thermal loads, which would come from a projected extension of the current building.