Refrigeration cycle apparatus having heat exchanger switchable between parallel and series connection

A refrigeration cycle apparatus comprising

• a refrigeration circuit in which non-azeotropic refrigerant mixture circulates,
• the refrigeration circuit comprising a compressor, a first heat exchanger, a second heat exchanger, an expansion valve, and a multi-way valve,
• the multi-way valve having (i) a first state in which the non-azeotropic refrigerant mixture flows in order of the first heat exchanger, the expansion valve, and the second heat exchanger, and (ii) a second state in which the non-azeotropic refrigerant mixture flows in order of the second heat exchanger, the expansion valve, and the first heat exchanger,
• the first heat exchanger comprising
• a plurality of refrigerant flow paths, and
• a linear flow path switching device valve configured to switch connections of the plurality of refrigerant flow paths between (a) a series state in which the non-azeotropic refrigerant mixture flows through the plurality of refrigerant flow paths in series and (b) a parallel state in which the non-azeotropic refrigerant mixture flows through the plurality of refrigerant flow paths in parallel,
• the refrigeration cycle apparatus further comprising
• a controller configured to switch the linear flow path switching valve between the series state and the parallel state when the multi-way valve is in the second state, wherein
• the controller is configured to, in switching of the connections of the plurality of refrigerant flow paths,
• maintain a connection state after the switching when a temperature difference between a refrigerant temperature at an inlet of the first heat exchanger and a refrigerant temperature at an outlet of the first heat exchanger decreases, and
• return the connection state after the switching to the connection state immediately before the switching when the temperature difference increases.