Abstract: A refrigeration cycle system includes: a heat source circuit including a secondary-side compressor, a cascade heat exchanger, a secondary-side switching mechanism, and a suction flow path; a plurality of utilization circuits respectively including utilization-side heat exchanger; a first communication pipe; a second communication pipe; a third communication pipe; a connection path; and a first on-off valve. The first communication pipe and the first heat source pipe connect the plurality of utilization-side heat exchangers and the secondary-side switching mechanism. The second communication pipe and the second heat source pipe connect the plurality of utilization-side heat exchangers and suction flow path. The third communication pipe, the fourth heat source pipe, and the fifth heat source pipe connect the plurality of utilization-side heat exchangers and the cascade heat exchanger. The connection path connects the first communication pipe and the second communication pipe.

Abstract: A refrigeration cycle apparatus includes a primary-side refrigerant circuit in which a first refrigerant circulates and a secondary-side refrigerant circuit in which a second refrigerant circulates. The primary-side refrigerant circuit includes a primary-side compressor, a primary-side flow path of a cascade heat exchanger, a primary-side heat exchanger, and a primary-side switching mechanism.

Abstract: A refrigeration cycle system includes a first cycle and a second cycle. The first cycle is connected with a first compressor, a cascade heat exchanger, a first expansion unit, and a first heat exchanger, and includes a first flow path that connects the first compressor to the cascade heat exchanger, a second flow path that connects the cascade heat exchanger to the first expansion unit, a third flow path that connects the first heat exchanger to the first compressor, and a bypass flow path that connects at least one of the first flow path and the second flow path to the third flow path. The second cycle includes the cascade heat exchanger. In a case of using the cascade heat exchanger as a radiator of the first cycle and a heat sink of the second cycle, the first compressor of the first cycle is started after a flow of a heat medium generates in the cascade heat exchanger in the second cycle.

Abstract: A valve opening circuit mounted on a heat pump device having a valve on a refrigerant circuit includes a DC electric path to which a DC voltage generated from an AC voltage for normal use is applied, a valve drive circuit that opens and closes the valve by using the DC voltage of the DC electric path, a control unit that acquires a control power source voltage based on the DC voltage of the DC electric path and controls the valve drive circuit, and a power feed port connected to the DC electric path and connectable to a DC power source line provided from outside for emergency. The control unit causes the valve drive circuit to open the valve when the AC voltage is lost and the DC voltage is fed from the DC power source line to the power feed port.

Abstract: An air-conditioning management system includes: an air conditioning apparatus configured to carry out a refrigerant recovery operation of recovering a refrigerant from a refrigerant circuit that connects an outdoor unit and an indoor unit and sending the recovered refrigerant to each recovery unit of the outdoor unit; and a control unit configured to make a determination whether all the recovered refrigerant is sendable to each recovery unit before a start of the refrigerant recovery operation by the air conditioning apparatus, and to output, when determining that all the recovered refrigerant is not sendable to each recovery unit, a command for notifying the determination.

Abstract: An outdoor unit 3 of an air conditioner 1 includes an outdoor control unit 31 having a first control mode and a second control mode different from each other as control modes of a refrigerant recovery operation for recovering a refrigerant of a refrigerant circuit 9. A flow rate of the refrigerant in the refrigerant circuit 9 in the first control mode is larger than a flow rate of the refrigerant in the refrigerant circuit 9 in the second control mode.

Abstract: An air conditioning apparatus is an air conditioning apparatus dedicated to cooling and includes a first circuit and a second circuit. The first circuit has an outdoor heat exchanger that cools a first refrigerant by outdoor air. In the second circuit, a first heat transfer medium that is cooled by exchanging heat with the first refrigerant that flows in the first circuit flows. The first refrigerant is a HFO refrigerant having a critical temperature higher than that of R32.