A system includes a pressure exchanger (PX). The PX is coupled to a motor that controls an operating speed of the PX. The system further includes a first pressure gauge configured to generate first pressure data indicative of a pressure of a fluid of a condenser. A first controller is to generate a first control signal based on the first pressure data. The motor of the PX is configured to adjust the operating speed of the PX based on the first control signal. The system further includes a pump. The system further includes a fluid density sensor for generating fluid density data associated with a first output fluid of the PX. A second controller is to generate a second control signal based on at least the fluid density data. The pump is to adjust an operating speed of the pump based on the second control signal.

An improved cryogenic cooling system is disclosed. The cryogenic cooling system comprises a pressure sensing system disposed at or near the cryocooler to provide a more accurate representation of the pressure of the working gas within the cryocooler. By utilizing pressure measurements at the cryocooler, the thermal performance and net cooling capacity of the system may be improved. This may also improve the life of the cryocooler. Further, in some embodiments, pressure sensing systems are disposed at both the compressor and the cryocooler. In these embodiments, performance issues and potential failures may be monitored.

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.

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.

An air conditioner switches between a normal refrigeration cycle and a defrosting refrigeration cycle, and includes: a refrigerant circuit that connects a first heat exchanger, a second heat exchanger, a radiation panel, and an expansion valve that regulates a flow rate of a refrigerant flowing through the radiation panel; and a controller that causes the air conditioner to switch between the normal refrigeration cycle and the defrosting cycle. During the normal refrigeration cycle, the radiation panel performs cooling or heating. During the defrosting cycle, the first heat exchanger serves as a radiator and the second heat exchanger serves as an evaporator. During the defrosting cycle, the controller causes the expansion valve to be in a fully closed state.

A hydrogen cooling apparatus according to an embodiment includes: a binary refrigeration unit including a high-temperature-side refrigerator and a low-temperature-side refrigerator; and a hydrogen-cooling-fluid circulation unit. The binary refrigeration unit cools a hydrogen cooling fluid circulated by the hydrogen-cooling-fluid circulation unit by means of a low-temperature-side evaporator of the low-temperature-side refrigerator. The high-temperature-side refrigerator includes: a high-temperature-side refrigeration circuit; and a high-temperature-side bypass circuit including: a high-temperature-side bypass flow path that extends from a part, which is downstream of a high-temperature-side compressor and upstream of a high-temperature-side condenser in the high-temperature-side refrigeration circuit, to a part, which is downstream of a high-temperature-side expansion valve and upstream of a high-temperature-side evaporator in the high-temperature-side refrigeration circuit; and a high-temperature-side opening and closing valve provided on the high-temperature-side bypass flow path. The high-temperature-side refrigerator opens the high-temperature-side opening and closing valve when a high-temperature-side refrigerant has an abnormal pressure.

A refrigeration cycle apparatus includes: a compressor, a first outdoor heat exchanger, and a second outdoor heat exchanger that; and a flow path switching mechanism configured to switch a flow direction of refrigerant compressed by the compressor in the refrigerant circuit. The first outdoor heat exchanger and the second outdoor heat exchanger are arranged to allow the refrigerant to flow in parallel in the refrigerant circuit. The refrigeration cycle apparatus further includes a flow rate adjustment mechanism configured to adjust an amount of refrigerant flowing through the second outdoor heat exchanger. When switching between a cooling operation and a heating operation, the flow path switching mechanism switches the flow direction of the refrigerant while the flow rate adjustment mechanism temporarily closes a refrigerant flow path to the second outdoor heat exchanger.

A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains is a small-GWP refrigerant.

A vehicle air-conditioning apparatus is provided which is capable of expanding an effective range of a dehumidifying and heating mode to achieve comfortable vehicle interior air conditioning. A control device (controller) executes a dehumidifying and heating mode to let a refrigerant discharged from a compressor 2 radiate heat in a radiator 4, let a part of the refrigerant flow from a bypass circuit (refrigerant pipe 13F) to an indoor expansion valve 8, and let the residual refrigerant flow through an outdoor expansion valve 6. In the dehumidifying and heating mode, the control device has a state of controlling the operation of the compressor 2, based on a heat absorber temperature Te and executes a radiator temperature priority mode which enlarges a capability of the compressor when heat radiation in the radiator is insufficient.

An air conditioning unit capable of performing a refrigeration cycle using a small-GWP refrigerant is provided. A refrigeration cycle apparatus (1, 1a to 1m) includes a refrigerant circuit (10) including a compressor (21), a condenser (23, 31, 36), a decompressing section (24, 44, 45, 33, 38), and an evaporator (31, 36, 23), and a refrigerant containing at least 1,2-difluoroethylene enclosed in the refrigerant circuit (10).