A method of cooling a refrigerant includes providing a condenser (200) including a condenser shell (202) that contains a condenser chamber (204), a condensing conduit (209), and a cooling conduit (217); condensing a refrigerant within the condenser chamber (204) from a vapour phase to a liquid phase by exchanging heat from the refrigerant in the condenser chamber (204) to a fluid in the condensing conduit (209); supplying a first portion of the condensed refrigerant to the cooling conduit (217) via a first expansion valve (310) such that the first portion of the refrigerant decreases in pressure and temperature before entering the cooling conduit (217); and cooling the refrigerant in the condenser chamber (204) by exchanging heat from the refrigerant in the condenser chamber (204) to the first portion of the refrigerant in the cooling conduit (217).

A heat pump system including a charge compensator having a liquid line port for an inflow of a refrigerant into the charge compensator and for an outflow of the refrigerant from the charge compensator. The heat pump system further includes an isolation valve configured to control flows of the refrigerant to and from the charge compensator through a liquid line piping of the heat pump system based on whether the heat pump system is operating in a cooling mode, a defrost mode, or a heating mode, where the liquid line port is fluidly coupled to the liquid line piping of the heat pump system.

A refrigerant leakage determination system capable of detecting leakage of refrigerant without requiring complicated processing is provided. A refrigerant leakage determination system is a refrigerant leakage determination system of a refrigeration cycle apparatus that includes a refrigerant circuit including a heat-source-side heat exchanger and has, as operating modes, a normal mode in which the heat-source-side heat exchanger is caused to function as an evaporator and a defrosting mode in which the heat-source-side heat exchanger frosted during a normal operation is defrosted. The refrigerant leakage determination system includes a processor configured to acquire defrosting information regarding a relationship between a normal operation period and the number of defrosting operations, and memory that stores the defrosting information. The processor is further configured to determine, based on the acquired defrosting information, leakage of refrigerant in the refrigerant circuit.

A method for controlling a vapour compression system (1) is disclosed. A mass flow of refrigerant along a part of the refrigerant path is estimated, based on measurements performed by one or more pressure sensors (10, 12, 13) for measuring a refrigerant pressure at selected positions along the refrigerant path and one or more temperature sensors (11, 14) for measuring a refrigerant temperature at selected positions along the refrigerant path. A refrigerant pressure or a refrigerant temperature at a selected position a pressure sensor (10, 12, 13) or temperature sensor (11, 14) along the refrigerant path is derived, based on the estimated mass flow. The vapour compression system (1) is allowed to continue operating, even if a sensor (10, 11, 12, 13, 14) is malfunctioning or unreliable.

A thermal management system includes an integrated open-circuit refrigeration system and closed-circuit heat pump system. The thermal management system includes a receiver having a first receiver port and a second receiver port, the receiver configured to store a refrigerant fluid, an evaporator having a first evaporator port and a second evaporator port, the heat pump circuit having a closed-circuit fluid path with the receiver and the evaporator and an open-circuit refrigeration system configured to receive refrigerant from the receiver, with the open-circuit refrigeration system having an open-circuit fluid path that includes the receiver and the evaporator.

Disclosed are a refrigerator cooling system and a method for defrosting a refrigerator. The refrigerator cooling system includes a refrigerant circulation flow path provided with a compressor, a condenser, a throttling device and an evaporator. The throttling device has a throttling working mode for cooling and a defrosting working mode not used for cooling. The throttling working mode and the defrosting working mode are switched with each other. The condenser has a first heat release mode corresponding to the throttling working mode and a second heat release mode corresponding to the defrosting working mode, and a heat release amount of a refrigerant flowing through the condenser in the second heat release mode is lower than a heat release amount of the refrigerant flowing through the condenser in the first heat release mode.

A multi-stage refrigeration system (100) includes: a refrigeration loop (110), which includes a gas suction port of a multi-stage compressor (111), a condenser (112), a first throttling element (113), an evaporator (114) and an exhaust port of the multi-stage compressor which are sequentially connected through pipelines; an economizer branch (120), which includes an economizer (121), a second throttling element (122) and a first control valve (123), the economizer having an economizer liquid inlet connected to the condenser via the first throttling element, an economizer liquid outlet connected to the evaporator via the second throttling element, and an economizer exhaust port connected to an intermediate stage of the multi-stage compressor via a control valve; and a bypass branch (130), which is joined to the evaporator from the downstream of the second throttling element and connected to the condenser via the first throttling element, and on which a second control valve (131) is arranged.

Provided is an air conditioning apparatus. The air conditioning apparatus includes a heat exchanger in which the refrigerant and the water are heat-exchanged with each other, a high-pressure guide tube extending from a high-pressure gas tube of an outdoor unit so as to be connected to one side of the heat exchanger, a low-pressure guide tube extending from a low-pressure gas tube of the outdoor unit so as to be combined with the high-pressure guide tube, a liquid guide tube extending from a liquid tube of the outdoor unit so as to be connected to the other side of the heat exchanger, a bypass tube configured to connect a bypass branch point of the high-pressure gas tube to a bypass combination point of the liquid guide tube to bypass a high-pressure refrigerant existing in the high-pressure tube to the liquid guide tube, and a bypass valve installed in the bypass tube.

A heat pump cycle includes a compressor, a heat exchanger, a gas-liquid separator, and an outdoor heat exchanger. The heat pump cycle includes a main circuit connecting the compressor, the heat exchanger, the gas-liquid separator, and the outdoor heat exchanger such that refrigerant flows therethrough. The heat pump cycle includes an exhaust-heat recovery heat exchanger, and an exhaust-heat recovery circuit forming a flow path leading to the compressor not through the outdoor heat exchanger but through the exhaust-heat recovery heat exchanger. The heat pump cycle includes an expansion valve that is disposed upstream of the exhaust-heat recovery heat exchanger in the exhaust-heat recovery circuit and expands the refrigerant such that the refrigerant changes from liquid phase to gas phase in the exhaust-heat recovery heat exchanger.

A refrigeration apparatus includes: a refrigerant circuit through which refrigerant circulates; a controller to execute a plurality of refrigerant shortage sensing functions of sensing a shortage of an amount of the refrigerant; and an input device through which an operation mode to be set is input into the controller. The operation mode includes: a first mode in which energy-saving performance is emphasized; and a second mode in which the refrigeration apparatus is permitted to operate in a range in which reliability is ensured. In accordance with the operation mode set through the input device, the controller determines which one of sensing results obtained by the refrigerant shortage sensing functions is enabled and which one of sensing results obtained by the refrigerant shortage sensing functions is disabled. When a sensing result determined to be enabled shows a refrigerant shortage, the controller gives a notification about the refrigerant shortage.