Experimental investigation of a modular heat pump for residential applications

Heat pumps are widely regarded as a key technology for sustainable heating, offering a pathway to significantly reduce fossil fuel dependency and combat the climate crisis. However, replacing individual gas boilers with heat pumps in multi-unit residential buildings remains a substantial challenge, despite its immense potential to lower urban greenhouse gas emissions. To address this, the Gasthermenersatz project aims to develop a compact, modular heat pump designed to replace conventional gas boilers. This thesis focuses on the building and testing of a prototype for such a modular heat pump system. The prototype supports multiple functionalities, including space heating, cooling, and domestic hot water production. Various configurations and operational modes were tested to identify the optimal design for the refrigerant circuit. Measurements were conducted across a range of operating points, comparing different heat pump modules to each other and to modules from a previous iteration. While efficiency improvements were anticipated due to the use of a new compressor type, the results did not align with expectations and were
partially inconclusive. To investigate these discrepancies, additional performance parameters were analyzed to pinpoint potential causes. The findings suggest that further research and testing are necessary to fully understand and resolve the
performance issues.