A showcase includes a refrigerant circuit and a refrigerant enclosed in the refrigerant circuit. The refrigerant circuit includes a compressor (121), a radiator (122), an expansion valve (123), and an evaporator (124). The refrigerant is a low-GWP refrigerant.

A refrigeration cycle device includes: a compressor having a compression mechanism forming a compression chamber for compressing refrigerant, and a cooled portion cooled by the refrigerant before being compressed by the compression mechanism; a radiator that radiates the refrigerant compressed by the compressor; a decompressor that decompresses the refrigerant radiated by the radiator; an evaporator that evaporates the refrigerant decompressed by the decompressor; an acquisition unit that acquires the state of the refrigerant after cooling the cooled portion and before flowing into the compression chamber; and a control unit that controls the superheat degree of the refrigerant flowing into the compression chamber based on the state of the refrigerant acquired by the acquisition unit.

An HVAC system is disclosed, comprising: (a) a compressor, (b) a source heat exchanger for exchanging heat with a source fluid, (c) a first load heat exchanger operable for heating/cooling air in a space, (d) a second load heat exchanger for heating water, (e) first and second reversing valves, (f) first and second 3-way valves, (f) a bi-directional electronic expansion valve, (g) a first bi-directional valve, and (h) a second bi-directional valve to modulate exchange of heat in the first load heat exchanger when operating as an evaporator and to control flashing of the refrigerant entering the source heat exchanger when operating as an evaporator, (h) a source pump for circulating the source fluid through the first load heat exchanger, (i) a water pump for circulating water through the second load heat exchanger, and (j) a controller to control operation of the foregoing.

A refrigeration cycle apparatus includes: a refrigerant circuit in which a compressor, a condenser, an expansion device, and an evaporator are connected by pipes, and refrigerant circulates; a high-pressure sensor that detects a pressure of the refrigerant on a discharge side of the compressor; a first temperature sensor that detects a temperature of the refrigerant on an outlet side of the condenser; and a controller that determines that the high-pressure sensor is abnormal, when the compressor is in operation and the temperature detected by the first temperature sensor is higher than a saturated liquid temperature or a saturated gas temperature that is calculated from the pressure detected by the high-pressure sensor.

A method for operating and controlling a vapor-compression cycle includes providing a system comprising an evaporator with a fan, a compressor, a condenser with a fan, an integrated expander, and a flash tank device with a vapor/liquid two-phase inlet and two outlets wherein a first outlet is a vapor outlet and a second outlet is a liquid outlet, and a metering valve; bringing a vapor-compression cycle up to steady-state at a fixed operating condition; opening the metering valve until the desired compressor suction superheat is achieved; and maintaining the desired degree of superheat by selectively increasing and decreasing superheat by reducing and increasing metering valve flow rate respectively.

When an ejector having a variable nozzle and a variable throttle mechanism are integrated together as an ejector module, a nozzle-side central axis CL1 and a decompression-side driving mechanism have a twisted positional relationship, if the nozzle-side central axis CL1 is defined as a central axis of a nozzle-side driving mechanism in a displacement direction in which the nozzle-side driving mechanism of the ejector having the variable nozzle displaces a needle valve, and the decompression-side central axis CL2 is defined as a central axis of a decompression-side driving mechanism in a displacement direction in which the decompression-side driving mechanism of the variable throttle mechanism displaces a throttle valve. When viewed from the central axis direction of one of the nozzle-side central axis CL1 and the decompression-side central axis CL2, a driving portion corresponding to the one central axis is disposed to overlap with the other central axis.

A heating, ventilation, air conditioning, and/or refrigeration (HVAC&R) system includes a first vapor compression flow path having a first condenser configured to place a working fluid in a heat exchange relationship with a cooling fluid, a second vapor compression flow path having a first evaporator configured to place the working fluid in a heat exchange relationship with a conditioning fluid, and a shared vapor compression flow path having a second condenser configured to place the working fluid in a heat exchange relationship with the cooling fluid and a second evaporator configured to place the working fluid in a heat exchange relationship with the conditioning fluid. The first vapor compression flow path is configured to direct working fluid vapor from the second evaporator to the first condenser and the second vapor compression flow path is configured to direct working fluid liquid from the second evaporator to the first evaporator.

A refrigeration system includes a dedicated defrost-mode compressor that delivers high pressure, high temperature refrigerant to one or more evaporators to defrost the evaporators.

A refrigeration system includes an expansion valve downstream of one or more medium temperature compressors. The expansion valve is configured to decrease pressure of a portion of refrigerant output by the one or more medium temperature compressors. When defrost operation of an evaporator is indicated, the refrigerant with decreased pressure from the expansion valve is provided to the evaporator for at least a period of time sufficient to defrost the evaporator.

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.