A system has a compressor, a heat rejection heat exchanger, first and second ejectors, first and second heat absorption heat exchangers, and a separator. The ejectors each have a primary inlet coupled to the heat rejection exchanger to receive refrigerant. A second heat absorption heat exchanger is coupled to the outlet of the second ejector to receive refrigerant. The separator has an inlet coupled to the outlet of the first ejector to receive refrigerant from the first ejector. The separator has a gas outlet coupled to the secondary inlet of the second ejector to deliver refrigerant to the second ejector. The separator has a liquid outlet coupled to the secondary inlet of the first ejector via the first heat absorption heat exchanger to deliver refrigerant to the first ejector.

A channel on an upstream side of a third expansion device and a channel on an upstream side of a second expansion device are connected during a heating operation, and medium pressure refrigerant generated by the third expansion device during the heating operation is introduced on a suction side of a compressor via the second expansion device and a suction injection pipe.

One aspect presents a controller that comprises a control board, a microprocessor located on and electrically coupled to the control board, and a memory coupled to the microprocessor and located on and electrically coupled to the control board. The controller is configured to receive an operating parameter signal and recalculate a first maximum heating % demand to a second maximum heating % demand that is greater than the first maximum heating % demand, when a value of the operating parameter signal exceeds a predetermined value, and operate the HP system based on the second maximum heating % demand.

A compound valve includes a body having a valve chamber; a cylindrical-shaped valve element having opening portions in its lateral side surface for allowing heat media to flow inside of the valve element, and a partition member there inside in the longitudinal direction; and a motor for controlling a rotation angle of the valve element, and the opening portions communicate with either one of a first heat-medium inflow port or a second heat-medium inflow port, and with either one of a third heat-medium outflow port or a fourth heat-medium outflow port; two heat media having different properties flow adjacent to the partition member; and, by controlling, by a rotation angle of the motor, areas of the communicating inflow ports and the opening portions, and those of the communicating outflow ports and the opening portions, the quantities of flow are controlled.

A refrigerant that has flowed out of a liquid ejector radiates heat in a radiator, and a liquid-phase refrigerant that has radiated heat in the radiator flows into an ejection refrigerant passage of the liquid ejector. A discharged refrigerant of a compressor that suctions the refrigerant that has flowed out of a low-pressure evaporator flows into an inflow refrigerant passage of the liquid ejector. An ejector adopted as the liquid ejector is one in which an ejection refrigerant is ejected from the ejection refrigerant passage to a gas-liquid mixing portion, and the ejection refrigerant is ejected on an outer circumferential side of the inflow refrigerant flowing from the inflow refrigerant passage into the gas-liquid mixing portion.

A flow disturbance apparatus includes: a refrigerant pipe having a flow space in which refrigerant flows; and at least one disturbance member disposed inside the refrigerant pipe that is vibrated by the flow of refrigerant in the refrigerant pipe to disturb the refrigerant flowing in the refrigerant pipe.

A system has a first compressor and a second compressor. A heat rejection heat exchanger is coupled to the first and second compressors to receive refrigerant compressed by the compressors. The system includes an economizer for receiving refrigerant from the heat rejection heat exchanger and reducing an enthalpy of a first portion of the received refrigerant while increasing an enthalpy of a second portion. The second portion is returned to the compressor. The ejector has a primary inlet coupled to the means to receive a first flow of the reduced enthalpy refrigerant. The ejector has a secondary inlet and an outlet. The outlet is coupled to the first compressor to return refrigerant to the first compressor. A first heat absorption heat exchanger is coupled to the economizer to receive a second flow of the reduced enthalpy refrigerant and is upstream of the secondary inlet of the ejector. A second heat absorption heat exchanger is between the outlet of the ejector and the first compressor.

A system has a first compressor and a second compressor. A heat rejection heat exchanger is coupled to the first and second compressors to receive refrigerant compressed by the compressors. The system includes an economizer for receiving refrigerant from the heat rejection heat exchanger and reducing an enthalpy of a first portion of the received refrigerant while increasing an enthalpy of a second portion. The second portion is returned to the compressor. The ejector has a primary inlet coupled to the means to receive a first flow of the reduced enthalpy refrigerant. The ejector has a secondary inlet and an outlet. The outlet is coupled to the first compressor to return refrigerant to the first compressor. A first heat absorption heat exchanger is coupled to the economizer to receive a second flow of the reduced enthalpy refrigerant and is upstream of the secondary inlet of the ejector. A second heat absorption heat exchanger is between the outlet of the ejector and the first compressor.

A refrigeration system, when a set evaporator water outlet temperature T.sub.o is less than a daily minimum temperature T.sub.min, starts a cold water unit to cool a cooling pool; when the set evaporator water outlet temperature T.sub.o is greater than a daily maximum temperature T.sub.max, starts a natural cooling source to cool the cooling pool; when T.sub.min≤T.sub.o≤T.sub.max, if T.sub.i≥T.sub.o−a set value, starts the cold water unit to cool the cooling pool, and if T.sub.i<T.sub.o−the set value, starts the natural cooling source to cool the cooling pool. The refrigeration system not only satisfies the cooling requirements of the cooling pool, but also achieves the purpose of saving energy, reducing costs.

A heat exchange unit includes a heat exchanger including a plurality of heat transfer tubes and a plurality of refrigerant distributors. Each of the plurality of refrigerant distributors includes an inlet pipe through which refrigerant flows into the refrigerant distributor and a plurality of distribution pipes through which the refrigerant flows out of the refrigerant distributor. Each of the plurality of distribution pipes is connected to a corresponding one of the plurality of heat transfer tubes. The inlet pipe of the refrigerant distributor having a relatively low average value of levels of the plurality of distribution pipes connected to the plurality of heat transfer tubes has a smaller inside diameter than the inlet pipe of the refrigerant distributor having a relatively high average value of levels of the plurality of distribution pipes connected to the plurality of heat transfer tubes.