The present disclosure provides a compressor with an oil equalizing pipe, a parallel compressor set, and an oil equalizing method. The compressor includes at least one oil equalizing pipe, an opening at one end of the oil equalizing pipe is formed in a target oil level of an oil sump, and the opening at the other end of the oil equalizing pipe is formed in a suction port; and when the oil level of the oil sump of the compressor is higher than the target oil level, the extra oil enters the suction port through the oil equalizing pipe. Compared with the prior art, the present disclosure has the advantages that, when the compressor is running, the gas in the suction port flows, so that the pressure at the suction port is less than the pressure on the surface of the oil sump; when the oil level of the oil sump of the compressor is higher than the target oil level, the extra oil enters the suction port through the oil equalizing pipe under the action of the above pressure difference, a part of the oil enters vortex and is discharged from the compressor via the exhaust port, and the oil discharged from the compressor returns to the other compressor lack of oil through a pipeline, thereby achieving oil balance between different compressors.

A refrigeration apparatus includes first and second refrigeration circuits, and a supercooling circuit. The supercooling circuit includes a supercooling bypass flow path which communicates a part of the first refrigeration circuit positioned on the downstream side of the condenser and on the upstream side of the first expansion valve, to a compressor on the first refrigeration circuit; a supercooling control valve; and a supercooling heat exchanger disposed on the downstream side of the supercooling control valve in the supercooling bypass flow path. The supercooling heat exchanger is configured to cool the refrigerant flowing through a part of the first refrigeration circuit, on the downstream side of a connection position to the supercooling bypass flow path. The second refrigeration circuit includes: a branch flow path which branches from a part of the first refrigeration circuit, on the upstream side of the connection position to the supercooling bypass flow path.

Methods for shortening the cycle time in each of the defrost, standby and cool modes of operation of a very low temperature refrigeration system. These methods can be used alone or in combination with one or more of each of the other techniques, including, for example, in a single very low temperature refrigeration system, to provide a fast total cycle of one, two or all three of the defrost, standby and cool modes.

In a heat pump cycle device, a flow passage switching portion includes a flow passage switching valve body configured to open and close a cooling side flow passage. A refrigerant circulation circuit includes a low-pressure flow passage through which a low-pressure refrigerant decompressed by a first decompressor flows toward a compressor in a heating mode, and a pre-evaporator flow passage provided between the flow passage switching valve body and a refrigerant inlet of an evaporator. The flow passage switching portion causes a pre-evaporator flow passage to communicate with the low-pressure flow passage while bypassing the evaporator when a refrigerant pressure in the low-pressure flow passage is lower than a refrigerant pressure in the pre-evaporator flow passage, in the heating mode.

An air conditioning apparatus includes an outdoor device that is configured to circulate refrigerant and that includes a compressor and an outdoor heat exchanger, a plurality of indoor devices configured to circulate water, and a heat exchange device that connects the outdoor device with the indoor device. The heat exchange device includes a heat exchanger configured to exchange heat between the refrigerant and the water, and a switch device configured to control flow of refrigerant between the indoor device and the heat exchanger.

A thermo-hygrostat air conditioner is provided that may include at least one indoor unit installed indoors, and including a main coil that provides air that meets a predetermined humidity by dehumidifying outdoor air and a sub coil that cools or heats the dehumidified air at a predetermined temperature and provides the air indoors; and an outdoor unit connected to the main coil and the sub coil of the indoor unit via a refrigerant pipe and including at least one outdoor heat exchanger, at least one compressor, at least one outdoor expansion valve and at least one four way valve. A mode of the main coil and the sub coil may be determined depending on a cooling load and a heating load. The outdoor unit may control the four way valve according to the mode of the main coil and the sub coil and provide refrigerant to the main coil and the sub coil according to the mode.

A refrigeration system includes a rotary pressure exchanger fluidly coupled to a low pressure branch and a high pressure branch. The rotary pressure exchanger is configured to receive the refrigerant at high pressure from the high pressure branch, to receive the refrigerant at low pressure from the low pressure branch, and to exchange pressure between the refrigerant at high pressure and the refrigerant at low pressure, and wherein a first exiting stream from the rotary pressure exchanger includes the refrigerant at high pressure in the supercritical state or the subcritical state and a second exiting stream from the rotary pressure exchanger includes the refrigerant at low pressure in the liquid state or the two-phase mixture of liquid and vapor.

A dynamic receiver is included in parallel to an expander of a heating, ventilation, air conditioning, and refrigeration (HVACR) system. The dynamic receiver allows control of the refrigerant charge of the HVACR system to respond to different operating conditions. The dynamic receiver can be filled or emptied in response to the subcooling observed in the HVACR system compared to desired subcooling for various operating modes. The flow through an expander of the HVACR system can be controlled to account for the mass flow rate through an outlet valve of the dynamic receiver when the dynamic receiver is emptied, preventing or reducing instability or effects on system parameters such as the suction superheat.

A system includes a heat exchanger mounted to the brackets and receiving cryogen, the heat exchanger having a vertical inlet coupled in parallel to a plurality of equal size horizontal tubes each traversing a width of the heat exchanger and further coupled in parallel to a vertical outlet pipe with an outlet diameter at least twice an inlet tube diameter; a temperature sensor; a thermostat that monitors the temperature sensor and maintains a predetermined temperature set point by communicating with a solenoid valve coupled to the heat exchanger; an exhaust line coupled to the outlet pipe that expels exhaust gas outside the enclosed facility; multiple fans attached to the heat exchanger; and a fail-safe oxygen sensor to protect a biological object in the enclosed facility.

A transport climate control system for a climate controlled transport unit includes a main heat transfer circuit and a chiller heat transfer circuit. The main heat transfer circuit includes a compressor, a condenser, a main expansion valve, a main evaporator, a chiller expansion valve, and a chiller evaporator. The main evaporator and a chiller evaporator positioned are in parallel to each other downstream of the condenser. Working fluid and a second process fluid flowing through the main evaporator. Working fluid and a third process fluid flowing through the chiller evaporator. The chiller heat transfer circuit includes the chiller evaporator and the third process fluid is configured to provide auxiliary cooling. A method of operating a transport climate control system for a climate controlled transport unit includes operating in a HVACR and chiller mode, operating in a HVACR mode, and operating a chiller mode.