Propane-based heat pump solutions for existing multi family houses - requirements and possible system solutions

Approximately 40% of the living area in Germany can be attributed to multi-family houses, a large share of which are existing buildings heated with fossil fuels. To decarbonize these with heat pumps, the housing industry needs standardized solutions for refurbishment. Therefore, this study compiles essential boundary conditions from the housing stock such as required capacity for heating and domestic hot water preparation, required condenser outlet temperatures, available installation space, permissible acoustic emissions, safety measures. On this basis three different heat pump solutions based on the future-proof low-GPW refrigerant propane (R290) are outlined: apartment-wise heating systems (currently typically consisting of wall-hung gas boilers), central heating systems, heat pump installed indoors, central heating systems, air-source heat pump installed outdoors (direct evaporation).