A refrigerant flow path switching device includes: a first header pipe that is connected to a high-and-low-pressure gas connection pipe of a heat source unit in an air conditioner; a second header pipe that is connected to a sucked-gas connection pipe of the heat source unit; a third header pipe that is connected to a liquid connection pipe of the heat source unit; switching units that each correspond respectively to utilization units in the air conditioner and include valves that control refrigerant flows; and a casing accommodating the first header pipe, the second header pipe, the third header pipe, and switching units. The refrigerant flow path switching device switches among refrigerant flow paths, each of which is between the heat source unit and one of the utilization units.

A defrosting control method of a multi-functional multi-split system with double four-way valves. The multi-functional multi-split system includes an outdoor unit, at least one set of hydraulic modules, and at least one set of indoor modules. When the multi-split system is switched from a normal operation mode to a defrosting mode, a first four-way valve and a second four-way valve are powered down, and operation modes of each set of indoor modules and each set of hydraulic modules, the on/off state of fans of an indoor heat exchanger and a hydraulic heat exchanger, opening degrees of a first electromagnetic valve of the indoor heat exchanger and a second electromagnetic valve of the hydraulic heat exchanger, and the on/off state of the first electromagnetic valve and the second electromagnetic valve are correspondingly adjusted based on the previous operation modes of each set of indoor modules and each set of hydraulic modules.

A refrigeration apparatus includes a gas-liquid separator on a downstream side of a radiator, and a refrigerant circuit in which a high pressure of a refrigeration cycle is equal to or higher than a critical pressure. The refrigeration apparatus includes a gas passage that communicates with the gas-liquid separator and at least one of a plurality of heat exchangers provided in the refrigerant circuit, and an opening and closing device that opens and closes the gas passage. There is provided a controller that opens the opening and closing device when a pressure in the gas-liquid separator is equal to or higher than a predetermined value in a state where a compression unit of the refrigerant circuit is stopped to suppress occurrence of pressure abnormality inside the gas-liquid separator in a state where a compressor is stopped.

Systems and methods have demonstrated the capability of rapidly cooling the contents of pods containing the ingredients for food and drinks.

A valve for a refrigeration system and a method of forming a valve includes a dual piston assembly having an inner piston (44) and an outer piston (42) that are moveable relative to each other to control pressure equalization flow through the valve, and an adjustable control stem (66) engageable with the outer piston that enables a low fluid equalization flow when in a first position and a variably higher fluid equalization flow when in a variable second position. The inner piston has a plurality of bleed orifices (46, 48) that are openable by movement of the outer piston relative to the inner piston.

A method of shutting down a refrigeration system including: initiating a shutdown process of the refrigeration system; closing a first valve within a refrigerant circuit of the refrigeration system; operating a compressor within the refrigerant circuit; detecting a suction pressure within the refrigerant circuit; closing a second valve within the refrigerant circuit of the refrigeration system when the suction pressure is below a threshold suction pressure; and stopping operation of the compressor.

A refrigeration cycle apparatus includes: a refrigerant circuit; an oil reservoir; a first pipe that connects the oil separator and the oil reservoir, the first pipe being configured to send the refrigeration oil separated by the oil separator to the oil reservoir; a first valve provided at the first pipe; a second pipe that connects the oil reservoir and a suction side of the compressor; a second valve provided at the second pipe; a third pipe that connects the oil reservoir and the suction side of the compressor at a position lower than a position at which the second pipe is connected to the oil reservoir; and a third valve provided at the third pipe. The first to third valves are closed in a non-operational period of the compressor.

An air-conditioning apparatus includes: a plurality of heat source units each including a compressor, a heat-source-side heat exchanger, a flow control valve, and an accumulator; a use-side load connected to the heat source units by pipes, and including a use-side heat exchanger that causes heat exchange to be performed between refrigerant supplied from each of the heat source units and a use-side heat medium; and a controller that controls an operation of each of the heat source units. The controller includes a determination unit and a liquid equalization unit. The determination unit determines whether or not a current operation is a non-normal operation in which the heat source units and the use-side load operate in a different manner from that in a heating operation or a cooling operation. The liquid equalization unit equalizes the amounts of liquid refrigerant that flows in the heat source units, when the determination unit determines that the current operation is the non-normal operation.

An air conditioner is provided that may include an outdoor unit having a compressor configured to compress a refrigerant; at least one indoor unit having an indoor heat exchanger, in which the refrigerant is heat exchanged, an indoor expansion valve that expands the refrigerant by adjusting an opening thereof, and a leak sensor that senses leakage of the refrigerant; a gaseous line that connects the outdoor unit and the at least one indoor unit and through which gaseous refrigerant flows; a liquid line that connects the outdoor unit and the at least one indoor unit and through which liquid refrigerant flows; a first shut-off valve disposed adjacent to the at least one indoor unit that opens and closes the gaseous line; a second shut-off valve disposed adjacent to the at least one indoor unit that opens and closes the liquid line; a supercooling pipe branched from the liquid line and connected to an inlet of the compressor; a supercooling expansion valve that expands refrigerant, flowing through the supercooling pipe, by adjusting an opening thereof; and a controller configured to control operation of the compressor and to control opening and closing of the first shut-off valve, the second shut-off valve, the indoor expansion valve, and the supercooling expansion valve. When the leak sensor senses the leakage of the refrigerant, the controller closes the first shut-off valve and the second shut-off valve.

A vehicular heat management system is provided with a heat pump type refrigerant circulation line that cools and heats specific air conditioning regions by generating a hot air or a cold air depending on a flow direction of a refrigerant. The system includes a compressor configured to suck, compress and discharge the refrigerant, a high-pressure side heat exchanger configured to dissipate heat of the refrigerant discharged from the compressor, an outdoor heat exchanger configured to allow the refrigerant to exchange heat with an air outside the vehicle, an expansion valve configured to depressurize the refrigerant flowing out of the high-pressure side heat exchanger or the outdoor heat exchanger, and one or more low-pressure side heat exchangers configured to evaporate the depressurized refrigerant. The outdoor heat exchanger and the low-pressure side heat exchangers are connected in series or in parallel depending on an air conditioning mode.