Method for operating heat pump system for air conditioning of e.g. building, involves determining mass flow of refrigerant by e.g. determining actual pressure difference of refrigerant between vaporization pressure and condensation pressure

摘要

The method involves circulating a refrigerant in a closed refrigerant circuit (1). The refrigerant is condensed in a heat exchanger (2) and expanded in an expansion valve (8) i.e. standardized pattern valve. The refrigerant is vaporized in an air refrigerant heat exchanger (3) and compressed in a compressor (10). Mass flow of the refrigerant is determined by determining an actual pressure difference of the refrigerant between vaporization pressure and condensation pressure and by determining current cross-section of an opening of the valve and density of the refrigerant entering the valve.