An air-conditioning apparatus includes a primary-side circuit in which a compressor, a first flow switching device, an outdoor heat exchanger, a second flow switching device, a first expansion device, and a relay heat exchanger are connected by pipes and in which refrigerant circulates; a secondary-side circuit in which the relay heat exchanger, a pump, a plurality of indoor heat exchangers, and heat medium flow control devices are connected by pipes and in which a heat medium circulates; and a controller configured to control the first and second flow switching devices such that in cooling and heating operations, the refrigerant and a heat-source-side fluid flow through the outdoor heat exchanger in opposite directions and the refrigerant flows through the relay heat exchanger in a constant direction. The pump is installed such that the heat medium, the refrigerant flow, and air for an air-conditioning target space flow in particular directions.

Leakage of a heating medium from a condenser or an evaporator can be quickly detected by a simple structure. A refrigeration apparatus 1 according to the present invention is formed by connecting a compressor 11, a condenser 12, an expansion valve 13 and an evaporator 14 by a pipe 15 such that a heating medium circulates therethrough in this order. The refrigeration apparatus 1 further includes a pressure detection unit 31, 32 that detects a pressure of the heating medium flowing through the pipe 15, and a control unit 41 that determines that leakage of the heating medium from the condenser 12 or the evaporator 14 has occurred, when a pressure detected by the pressure detection unit 31, 32 becomes not more than a predetermined value.

Cooling systems and methods of operation are provided. The cooling system may include a two-phase pumped loop (TPPL). The two-phase pumped loop may include, a receiver, a pump downstream from the receiver, a heat load downstream from the pump, a TPPL tee downstream from the heat load, a TPPL check valve downstream from the TPPL tee, and a heat exchanger downstream from the TPPL check valve and upstream from the receiver. The cooling system may further include a vapor cycle system (VCS) loop. The vapor cycle system loop may include the receiver, a compressor downstream from a vapor outlet of the receiver, a compressor check valve downstream from the compressor and upstream of the heat exchanger, the heat exchanger, and the heat load downstream from a liquid outlet of the receiver.

A method for controlling a vapour compression system (1) is disclosed, the vapour compression system (1) comprising at least one compressor (2, 16), a heat rejecting heat exchanger (3), a high pressure expansion device (4, 15, 17), a receiver (5), an evaporator expansion device (6), an evaporator (7) and a gas bypass valve (8), arranged in a refrigerant path. It is registered that the gas bypass valve (8) is malfunctioning or saturated, and a pressure value for a pressure prevailing inside the receiver (5) is obtained. Finally, the vapour compression system (1) is controlled in order to control a gaseous refrigerant supply to the receiver (5) to adjust the pressure prevailing inside the receiver (5) to reach a target pressure level.

A refrigeration cycle apparatus in which working refrigerant is a zeotropic refrigerant mixture containing at least a first refrigerant and a second refrigerant having a higher boiling point than the first refrigerant at the same pressure, the refrigeration cycle apparatus including at least a main passage in which a compressor, a first heat exchanger, a first expansion valve, and a second heat exchanger are sequentially connected, the first refrigerant having a property of disproportionation, the first refrigerant having a smaller composition ratio in the compressor than a composition ratio of the first refrigerant passing through the main passage.

A control method for cooling a refrigerant of an inverter includes the steps of: sucking a portion of the refrigerant out from a reservoir of a condenser in a chiller into a cooling plate of the inverter for cooling; according to a pressure value of the condenser and an outlet pressure value of the inverter, determining a set condition; and, based on the set condition, controlling an opening of an electronic expansion valve to adjust a flow of the portion of the refrigerant in the cooling plate of the inverter. In addition, a refrigerant bypass pipeline of the inverter is also provided.

A transport refrigeration system includes a compressor, a heat rejection heat exchanger, a flash tank, an expansion device and a heat absorption heat exchanger arranged in a serial refrigerant flow order to circulate a refrigerant; a controller configured to: determine a presence of at least one condition of the transport refrigeration system; and initiate a low refrigerant charge detection process in response to detecting the presence of the at least one condition of the transport refrigeration system.

This air conditioning device for a vehicle has: an indoor condenser; an indoor evaporator; a first expansion valve; a second expansion valve; a refrigerant line; an expansion valve control detector; and a controller. The expansion valve control detector is constituted by: only one temperature sensor that detects the temperature of refrigerant in an inter-expansion valve line of the refrigerant line; and only one pressure sensor that detects the pressure of the refrigerant in the inter-expansion valve line. During a cooling operation, the controller issues, to the first expansion valve, an opening command corresponding to a state quantity of the refrigerant that has been detected by the expansion valve control detector, and during a heating operation, the controller issues, to the second expansion valve, an opening command corresponding to a state quantity of the refrigerant that has been detected by the expansion valve control detector.

A bypass line is described that is capable of equalizing pressure within an HVAC system. The bypass line can also cause less noise than other solutions. A bypass line under the present disclosure can comprise a line from a high pressure side to a low pressure side of an HVAC system. Valves and orifices can be disposed within the bypass line. The valves and orifices help to slow the speed of fluid from high pressure to low pressure locations, thus reducing noise during pressure equalization.

A control valve of an embodiment includes a disc coaxially in contact with a diaphragm, and a shaft configured to transmit a drive force in an axial direction caused by displacement of the diaphragm to a valve element. The diaphragm has a corrugated portion between a flat portion and the outer peripheral portion, the flat portion having a contact surface with which the disc is in contact. The corrugated portion includes substantially N+0.5 corrugations (N being a natural number) each protruding relative to a reference surface, the corrugations being formed between the outer peripheral portion and the flat portion, the reference surface being one surface of the outer peripheral portion. A height of each of the N corrugations of the corrugated portion is smaller than a height of the flat portion, the heights each being a height relative to the reference surface in an unloaded condition.