A showcase includes a refrigerant circuit and a refrigerant enclosed in the refrigerant circuit. The refrigerant circuit includes a compressor (121), a radiator (122), an expansion valve (123), and an evaporator (124). The refrigerant is a low-GWP refrigerant.

Systems and methods for implementing ejector refrigeration cycles with cascaded evaporation stages that utilize a pump to optimize operation of the ejector and eliminate the need for a compressor between the evaporation stages.

A refrigeration apparatus for transport includes an electric component box that houses an inverter board and is arranged on a lateral side of an external heat exchanger. The electric component box has an opposing plate that faces an air entrance surface of the external heat exchanger. A heat sink is provided on the opposing plate of the electric component box. The heat sink is exposed to the outside of the electric component box to cool a power module on the inverter board.

A dual reclaim coil with a smart control application is provided that allows the refrigerant inlet to the HVAC unit switch between the two sides of the condenser is aimed to use the high temperature and pressure of the condenser/gas cooler outlet while a CO.sub.2 refrigerant system is operating above critical point. This occurs in hot ambient conditions, when the need for heating in the space is not as great as in the wintertime and the available heat at the condenser/gas cooler's outlet is sufficient to satisfy the heating load. This also mitigates space overcooling, while increasing the CO.sub.2 transcritical system's efficiency by subcooling the refrigerant for applications involving dehumidification HVAC systems which often results in a phenomenon called “overcooling” during the dehumidification season.

A cooling system includes a second receiver that receives refrigerant from a low side heat exchanger. A pipe connects the second receiver to a first receiver. A vapor portion of the refrigerant in the first receiver can flow through the pipe to the second receiver. A compressor is used to create a pressure differential in the second receiver relative to the first receiver such that the pressure in the first receiver is greater than the pressure in the second receiver. This pressure differential effectively acts as a pump that pushes the liquid refrigerant in the first receiver towards the low side heat exchanger.

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 heat source controller performs a first operation when a compression element is in a stopped state and a pressure in a receiver exceeds a predetermined first pressure. The heat source controller allows an inlet of the compression element to communicate with the receiver, and drives the compression element in the first operation.

Thermal management techniques include: transporting a refrigerant fluid from a receiver to an inlet of a flash tank that has a vapor-side outlet and liquid-side outlet such that a liquid phase of the refrigerant fluid moves to a bottom of the flash tank and outputs from the liquid-side outlet; forming a solid-vapor state from the liquid phase by expanding the liquid phase with an expansion valve to a first pressure that is less than a triple point pressure to form a solid-vapor mixture of the refrigerant fluid; extracting heat from a heat load with an evaporator that receives the solid-vapor mixture of the refrigerant fluid and sublimates the solid state of the solid-vapor mixture of the refrigerant fluid directly into a vapor phase of the refrigerant fluid; and discharging, from an exhaust line, the vapor phase to an ambient environment without returning the vapor phase to the receiver.

A method for an improved integration of refrigeration into conventional natural gas processing plants which use propane or similar hydrocarbon refrigerants either to supplement cooling by turbo-expanders or as the sole source of refrigeration.

A volume ratio control system for a compressor includes a chamber formed within a housing of the compressor, a piston disposed within the chamber, where the piston is configured to separate the chamber into at least a first portion fluidly coupled to a low pressure side of the compressor and a second portion fluidly coupled to a high pressure side of the compressor, and a biasing device disposed within the chamber, where the biasing device is configured to adjust a position of the piston in response to a pressure differential between the low pressure side of the compressor and the high pressure side of the compressor falling below a threshold value.