A storage assembly, which is in particular suitable for use in a cooling system designed for an operation with a two-phase coolant medium, comprising a storage container with a receiving area for receiving a coolant medium and a conveying device for conveying coolant medium from the receiving area of the storage container. The conveying device is formed integral with the storage container of the storage assembly.

A system and method for a CO.sub.2 refrigeration system includes a compressor, a heat exchanger, a liquid receiver, a first valve, and a valve controller. The heat exchanger operates as a gas cooler when the CO.sub.2 refrigeration system is in a transcritical mode and as a condenser when the CO.sub.2 refrigeration system is in the subcritical mode. The first valve controls a flow of refrigerant from the heat exchanger to the liquid receiver. The valve controller monitors an outdoor ambient temperature and a pressure of refrigerant exiting the heat exchanger, determines whether the CO.sub.2 refrigeration system is in the subcritical mode or in the transcritical mode, determines a pressure setpoint based on the monitored outdoor ambient temperature, and controls the first valve based on a comparison of the determined pressure setpoint and the monitored pressure when the CO.sub.2 refrigeration system is in the transcritical mode.

A refrigerant testing device and method for testing refrigerant diverted from a refrigeration system. The method comprises: diverting refrigerant from said refrigeration system to a container; changing a temperature of said refrigerant within said container; measuring a pressure and temperature of said refrigerant as said temperature changes; comparing said measured pressure and temperature values with reference values and where said comparing indicates a difference between said measured values and said stored reference values of more than a predetermined amount, generating a warning indication.

Described herein are techniques for coordinated operation of refrigerant climate control systems in an optimized manner. In an example process, climate control information for a plurality of refrigerant climate control systems is maintained. An energy optimization signal is received that describes a characteristic associated with an electrical energy source. A set of control signals is generated for a set of refrigerant climate control systems based on climate control information and the energy optimization information. The set of control signals is then sent to a set of refrigerant climate control systems. Each control signal may be configured to cause a respective refrigerant climate control system to operate using the electricity from the electrical energy source.