Efficiency in refrigerant charging work is addressed when a recovered refrigerant recovered from a first heat source unit is to be charged to a second heat source unit. A refrigerant charging method is a charging method used when a first heat source unit of an already installed refrigeration cycle apparatus in which a refrigeration cycle is to be performed by a refrigerant that circulates is to be replaced with a second heat source unit. The refrigerant charging method includes recovering a first refrigerant from an already installed refrigeration cycle apparatus and obtaining a recovered refrigerant and charging the recovered refrigerant and charging a second refrigerant whose composition differs from the composition of the recovered refrigerant to the refrigeration cycle apparatus after renewal that includes the second heat source unit.

A method of controlling injection into a compressor in a refrigeration cycle is described wherein the method is performed in a refrigeration cycle, which comprises at least a flash tank configured for receiving a refrigerant and separating liquid refrigerant and vapour refrigerant, and a compressor configured for compressing the refrigerant, wherein the compressor comprises a means for compressing, a suction port and an injection port, which is connected to the means for compressing for at least a time instance of the refrigeration cycle, wherein the flash tank is connected to the injection port of the compressor via an injection valve. The method comprises determining a pressure in the flash tank and controlling the injection valve based on the determined pressure in the flash tank.

A condenser subassembly for providing an economizer function in a refrigeration circuit, the condenser subassembly including: a condenser chamber 113; a flash tank chamber 114; an expansion device 117; and a housing, the housing defines a vessel 112a, the vessel comprising the condenser chamber 113 and the flash tank chamber 114, the condenser chamber 113 and the flash tank chamber 114 are separated from one another by a partition 115a in the vessel 112a and the expansion device 117 is arranged to pass condensed refrigerant from the condenser chamber 113 to the flash tank chamber 114.

Efficiency in refrigerant charging work is addressed when a refrigerant recovered from the first heat source unit is to be charged to a second heat source unit. In a refrigerant charging method in which a first heat source unit of an already installed refrigeration cycle apparatus in which a refrigeration cycle is to be performed by a refrigerant that circulates is replaced with a second heat source unit, transferring the refrigerant from the first heat source unit to the second heat source unit is included. In addition, the method includes measuring the weight of the refrigerant that is transferred from the first heat source unit to the second heat source unit.

A cooling apparatus includes: a first fluid flowpath including the following elements, in downstream flow sequence: a separator vessel; a subcooler having a first side in fluid communication with the first fluid flowpath and a second side configured to be disposed in thermal communication with a cold sink; a flow control valve; a primary evaporator assembly including at least one primary evaporator configured to be disposed in thermal communication with a primary heat load; and a pressure regulator operable to maintain a refrigerant saturation pressure within the primary evaporator at a predetermined set point.

A vapor compression system includes a heat exchanger configured to facilitate heat transfer between a refrigerant and a conditioning fluid. The vapor compression system also includes an expansion valve disposed along a conduit coupled to the heat exchanger. The conduit is configured to direct a flow of the refrigerant into the heat exchanger. Additionally, the vapor compression system includes a sensor configured to provide feedback indicative of a temperature of the conditioning fluid exiting the heat exchanger and a controller including a memory and processing circuitry. The processing circuitry is configured to receive a signal indicative of the temperature of the conditioning fluid exiting the heat exchanger from the sensor and adjust operation of the expansion valve based on the signal.

A liquid slug reduction and charge compensator device for use in air conditioning and heat pump systems includes a housing having a cavity. The housing includes an inlet port providing an entry path into the cavity and an outlet port providing an exit path from the cavity. The housing further includes a liquid line port providing a refrigerant pathway into and out of the cavity. The liquid slug reduction and charge compensator device further comprises a flash tube extending through the cavity and providing a passageway through the cavity such that a hot gas refrigerant that enters the cavity through the inlet port causes a liquid refrigerant that enters the flash tube to evaporate.

A system includes a high side heat exchanger, a flash tank, a first load, a second load, and a thermal storage tank. The high side heat exchanger is configured to remove heat from a refrigerant. The flash tank is configured to store the refrigerant from the high side heat exchanger and discharge a flash gas. The first load is configured to use the refrigerant from the flash tank to remove heat from a first space proximate to the first load. The second load is configured to use the refrigerant from the flash tank to remove heat from a second space proximate to the second load. The thermal storage tank is configured, when a power outage is determined to be occurring, to receive at least a portion of the flash gas from the flash tank, and remove heat from the flash gas.

A controller for a refrigeration system includes a processing circuit having one or more processors and memory. The processing circuit is configured to calculate a superheat of a gas refrigerant exiting a first side of a subcooler based on a measured temperature and a measured pressure of the gas refrigerant and compare the calculated superheat to a superheat threshold. In response to a determination that the calculated superheat is less than the superheat threshold, the processing circuit closes an expansion valve to restrict a flow of the gas refrigerant through a second side of the subcooler. In response to a determination that the calculated superheat is equal to or greater than the superheat threshold, the processing circuit operates the expansion valve to drive a temperature of a subcooled liquid refrigerant exiting the second side of the subcooler to a subcooled liquid temperature setpoint.

An apparatus includes a high side heat exchanger, a heat exchanger, a flash tank, a first expansion valve, a second expansion valve, a load, a first compressor, and a second compressor. During a first mode of operation, the second expansion valve directs refrigerant from the flash tank to the load. The refrigerant from the load bypasses the first compressor. The heat exchanger transfers heat from the refrigerant from the high side heat exchanger to the refrigerant from the load. The second compressor compresses the refrigerant from the heat exchanger. During a second mode of operation, the first expansion valve directs refrigerant from the flash tank to the load. The first compressor compresses the refrigerant from the load and the second compressor compresses the refrigerant from the first compressor before the refrigerant from the first compressor reaches the high side heat exchanger.