A refrigeration system, comprising an evaporator, a condenser, a throttling device, a compressor, an economizer and an ejector, these devices together form a closed-loop refrigerant circulation loop, the ejector being connected to the economizer, and the ejector being provided on an exhaust side of the compressor. The structure enables the refrigeration system to realize the dual-stage boost, does not affect the stability of the compressor due to the instability of the airflow of the ejector, and does not affect the oil property of the compressor, thereby ensuring the operation safety of the compressor.

A centrifugal compressor assembly is provided. The centrifugal compressor assembly includes a scroll assembly having a suction plate defining an inlet fluid passage, a suction plate housing, a diffuser plate, and a collector. The suction plate is detachably coupled to the suction plate housing, the suction plate housing is detachably coupled to the collector, and the diffuser plate is detachably coupled to the collector. The centrifugal compressor assembly further includes an impeller rotatably mounted in the scroll assembly for compressing fluid introduced through the inlet fluid passage, and a variable geometry diffuser system.

A refrigeration cycle apparatus (10) includes a refrigerant circuit (11) including a compressor (12), a heat source-side heat exchanger (13), an expansion mechanism (14), and a usage-side heat exchanger (15). In the refrigerant circuit (11), a refrigerant containing at least 1,2-difluoroethylene (HFO-1132 (E)) is sealed. At least during a predetermined operation, in at least one of the heat source-side heat exchanger (13) and the usage-side heat exchanger (15), a flow of the refrigerant and a flow of a heating medium that exchanges heating with the refrigerant are counter flows.

In an air conditioner that uses a refrigerant mixture containing at least 1,2-difluoroethylene, high efficiency is achieved. The motor rotation rate of a compressor (100) can be changed in accordance with an air conditioning load, and thus a high annual performance factor (APF) can be achieved. In addition, an electrolytic capacitor is not required on an output side of a rectifier circuit (21), and thus an increase in the size and cost of the circuit is suppressed.

In an air conditioner that uses a refrigerant mixture containing at least 1,2-difluoroethylene, high efficiency is achieved. In the air conditioner (1), a compressor (100, 200) can be driven without interposing a power conversion device between an AC power source (90, 190) and a motor (70, 170). Thus, it is possible to provide the air conditioner (1) that is environmentally friendly and has a relatively inexpensive configuration.

An air-conditioning unit that is able to suppress ignition at an electric heater even when leakage of refrigerant occurs while a low-GWP refrigerant is used is provided. In an outdoor unit (20) including a casing (60), a compressor (21) provided inside the casing (60) and configured to compress refrigerant containing 1,2-difluoroethylene, and a drain pan heater (54) provided inside the casing (60), an electric power consumption of the drain pan heater (54) is lower than or equal to 300 W.

A compressor and a refrigeration device are disclosed. The compressor has a sealing container, a motor portion and a compressing mechanism portion, and a bypass valve. The motor portion and the compressing mechanism portion are both provided in the sealing container. The compressor has an exhaust side and a suction side spaced apart from each other. The exhaust side is connected to the bypass valve. The exhaust side is suitable for exhausting air to external parts through the bypass valve, or suitable for communicating with the suction side through the bypass valve.

A heat source unit and a refrigeration cycle apparatus that are able to reduce damage to a connection pipe when a refrigerant containing at least 1,2-difluoroethylene is used are provided. An outdoor unit (20) that is connected via a liquid-side connection pipe (6) and a gas-side connection pipe (5) to an indoor unit (30) including an indoor heat exchanger (31) and that is a component of an air conditioner (1) includes a compressor (21) and an outdoor heat exchanger (23). A refrigerant containing at least 1,2-difluoroethylene is used as a refrigerant. A design pressure of the outdoor unit (20) is lower than 1.5 times a design pressure of each of the liquid-side connection pipe (6) and the gas-side connection pipe (5).

A turbo compressor includes a driving unit including a stator and a rotor that are configured to generate a rotational force and a rotary shaft that is connected to and rotated by the rotor, an impeller connected to the rotary shaft to pressurize a suction refrigerant in the radial direction of the rotary shaft and a casing that receives the driving unit and the impeller and supports the rotary shaft. The casing includes a first shell to which the stator is fixed and that rotatably supports the rotary shaft, and a second shell that is spaced apart from the first shell and surrounds the first shell. A shell passage is defined between the first and second shells. The discharged refrigerant cools the driving unit, which improves the efficiency of the compressor.

A compressor comprises a suction port configured to receive a refrigerant and means for compressing the refrigerant. The means for compressing forms at least one compression chamber, a discharge port configured for discharging the compressed refrigerant from the compressor, and a motor. The means for compressing comprises at least one opening for extracting a portion of the refrigerant from the at least one compression chamber and supplying the extracted portion of the refrigerant to the motor. A method comprises receiving a refrigerant at a suction port of the compressor, compressing the refrigerant in at least one compression chamber formed by a means for compressing of the compressor, discharging the refrigerant from the compressor at a discharge port of the compressor, and extracting a portion of the refrigerant from the at least one compression chamber and supplying the extracted portion of the refrigerant to a motor of the compressor.