A device for refuelling containers with pressurized gas, comprising a pressurized gas source, a transfer circuit intended to be removably connected to a container, the device comprising a refrigeration system for cooling the gas flowing from the gas source prior to its entering into the container, the refrigeration system comprising a refrigerant cooling loop circuit comprising, arranged in series, a compressor, a condenser section, an expansion valve and an evaporator section, the refrigeration system comprising a cold source in heat exchange with the condenser section and a heat exchanger located in the transfer circuit, the device comprising an electronic controller connected to the expansion valve and configured for controlling cooling power produced by the refrigeration system via the control of the opening of the expansion valve, the device comprising a differential temperature sensor system measuring the difference between the temperature of the refrigerant in the refrigerant cooling loop circuit at the outlet of the heat exchanger and the temperature of the refrigerant in the cooling loop circuit at the inlet of the heat exchanger, the electronic controller being configured for controlling the cooling power produced as a function of this temperature differential.

Described is a regulation apparatus for a refrigeration plant having defined therein a refrigerant fluid path and a plurality of devices arranged along the refrigerant fluid path. The regulation apparatus includes a first sensor arranged in a first point (P1) and a second sensor arranged in a second point (P3), each along the fluid path of the refrigeration plant, a control unit and an actuation device. The control unit controls a first value measured by the first sensor and obtains a first regulation request deriving from the first measured value as well as a second value measured by the second sensor and derives a second regulation request deriving from the second measured value, compares the first and second regulation requests, and establishes which regulation request is greater. The control unit also commands the actuation device to actuate the most effective regulation request of the refrigeration plant devices.

A heat pump includes an internal heat exchanger and a regulating device designed to bring the temperature of the working fluid at the outlet of a compressor to a specifiable minimum difference above the dew point at the same pressure. This allows the use of novel coolants in heat pumps, e.g., coolants having a low dew line slope of under 1000/kJ in the temperature-entropy diagram and characterized by very good safety and environmental properties.

The heat source controller transmits the drive permission signal (SE) to the utilization controller when the compression element is drivable. The utilization controller opens a utilization expansion valve when heat exchange in a utilization heat exchanger is required, on condition that the utilization controller receive the drive permission signal (SE).

A refrigeration system having a refrigerant circuit including a condenser, a flow control device, an evaporator, and a compressor connected in series. The compressor is configured to circulate a cooling fluid through the refrigerant circuit. The refrigerant circuit has an inlet line fluidly connecting the condenser to the evaporator and a suction line fluidly connecting the evaporator to the compressor. A heater is positioned to heat the cooling fluid during a defrost mode, and a pressure control is coupled to the refrigerant circuit downstream of the evaporator. In the defrost mode, the pressure control apparatus is configured to increase system pressure during the defrost mode to maintain flow of refrigerant into the evaporator and to control flow of cooling fluid to the compressor.

A method for controlling a vapour compression system (1) including a compressor unit (2) including one or more compressors (3, 12), a heat rejecting heat exchanger (4), a receiver (6), an expansion device (7) and an evaporator (8) arranged in a refrigerant path. A pressure value indicating a pressure prevailing inside the receiver (6) is obtained, and the obtained pressure value is compared to a first threshold pressure value. In the case that the obtained pressure value is below the first threshold pressure value, the compressor(s) (3, 12) of the compressor unit (2) are controlled in order to reduce a suction pressure of the vapour compression system (1).

A method for controlling operation of a refrigeration system (1), including one or more refrigeration entities (4), is disclosed. Each entity controller (7) obtains a measure for an error value between the measured value of a compressor control parameter and a setpoint value (8) for the compressor control parameter, and each entity controller (7) adjusts a refrigeration load of the corresponding refrigeration entity (4) to correspond to a cooling capacity of the compressor(s) (2), and in accordance with the obtained measure for an error value.

A heat pump system for conditioning regeneration air from a space is provided. The heat pump system is operable in a winter mode and/or a summer mode, and may be selectively operated in a defrost mode or cycle. During a defrost mode, hot refrigerant may be used to directly and sequentially defrost the regeneration air heat exchanger. A compressor may be configured to be overdriven during a defrost cycle.

A method for controlling suction pressure in a vapour compression system including one or more cooling entities is disclosed. For each cooling entity, a maximum required suction pressure and/or a required change in suction pressure for maintaining a target temperature in the refrigerated volume is obtained. A most loaded cooling entity among the one or more cooling entities is identified, based on the maximum required suction pressures and/or the required changes in suction pressure. The suction pressure of the vapour compression system is controlled in accordance with the maximum required suction pressure and/or required change in suction pressure for the identified most loaded cooling entity.

A method of operating a refrigeration cycle apparatus uses a compressor to compress a coolant. The compressed coolant is fed to a condenser for release of heat, the condensed coolant is later fed to a primary side of an internal heat exchanger for release of heat, and the cooled coolant is guided through an expansion device. The coolant expanded in the expansion device is fed to an evaporator for absorption of heat, the evaporated coolant is later fed to a secondary side of the internal heat exchanger for absorption of heat, and the heated coolant is fed to the compressor. For suction gas temperature control, an amount of heat transferred from the primary side to the secondary side of the internal heat exchanger is controlled with the aid of an additional expansion device arranged parallel to the heat exchanger and between the condenser and the evaporator.