A cooling system includes a first cooling loop, a second cooling loop and a heat exchanger configured to transfer heat from the first cooling loop to the second cooling loop. The first cooling loop includes a vapor/liquid separation feature configured to separate vapor present in the first cooling loop due to a leak between the first cooling loop and the second cooling loop. The first cooling loop also includes a pressure sensor configured to detect an increase in pressure in the first cooling loop that may result from a leak of second coolant into the first cooling loop.

A first valve is connected between a compressor and a first heat exchanger. A second valve is connected between the first heat exchanger and a expansion valve. When a start condition of the heating operation is satisfied and when a specific condition is satisfied, a controller starts supplying refrigerant from the compressor to the first valve, and then, opens the first and second valves. The specific condition is a condition indicating that a first heat exchange capability of the first heat exchanger is higher than a second heat exchange capability of a second heat exchanger. When the start condition of the heating operation is satisfied and when the specific condition is not satisfied, the controller opens the first and second valves, and then starts supplying the refrigerant from the compressor to the first valve.

An air conditioning system includes a main circuit having a multi-stage compressor, a condenser, a throttling element and an evaporator connected by pipelines; and a cooling branch, the inlet of which is connected to the main circuit between the condenser and the throttling element, and the outlet of which is connected to at least one of the first-stage suction port and the intermediate-stage suction port of the multi-stage compressor, wherein the cooling branch flows through the drive motor of the multi-stage compressor, and a regulating valve for controlling the opening of the cooling branch is provided on the cooling branch; and a control module that controls the opening of the regulating valve on the cooling branch based on the temperature of the outlet downstream of the drive motor on the cooling branch and the intermediate suction pressure of the intermediate-stage suction port of the multi-stage compressor.

A cooling system includes a first cooling loop, a second cooling loop and a heat exchanger configured to transfer heat from the first cooling loop to the second cooling loop. The first cooling loop includes a vapor/liquid separation feature configured to separate vapor present in the first cooling loop due to a leak between the first cooling loop and the second cooling loop. The first cooling loop also includes a pressure sensor configured to detect an increase in pressure in the first cooling loop that may result from a leak of second coolant into the first cooling loop.

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.

The present application provides apparatus (15) for connection to an HVAC-R system during maintenance or commissioning. The apparatus includes a plurality of ports (16, 17, 18) for fluid connection to the HVAC-R system and to maintenance apparatus, for example a refrigerant tank, a refrigerant recovery unit and/or a vacuum pump. The apparatus also includes a plurality of fluid connections (20) between the plurality of ports, each of the plurality of fluid connections having an electrically actuatable valve (21) to open and close the fluid connection. The apparatus also includes a control unit configured to control each of the electrically actuatable valves to configure the plurality of fluid connections.

A method for controlling a vapour compression system (1) is disclosed. A mass flow of refrigerant along a part of the refrigerant path is estimated, based on measurements performed by one or more pressure sensors (10, 12, 13) for measuring a refrigerant pressure at selected positions along the refrigerant path and one or more temperature sensors (11, 14) for measuring a refrigerant temperature at selected positions along the refrigerant path. A refrigerant pressure or a refrigerant temperature at a selected position a pressure sensor (10, 12, 13) or temperature sensor (11, 14) along the refrigerant path is derived, based on the estimated mass flow. The vapour compression system (1) is allowed to continue operating, even if a sensor (10, 11, 12, 13, 14) is malfunctioning or unreliable.

A cooling system including a vaporizer configured to absorb heat due to a liquid-phase refrigerant being vaporized, a condenser configured to discharge heat due to a refrigerant in a gaseous phase state being liquefied, a resistance body provided in a middle of a pipe passage ranging from the vaporizer to the condenser and applying a resistance to the refrigerant, state detection sensors provided in the pipe passage on an upstream and downstream sides of the resistance body and detecting a state of the refrigerant flowing through each side inside the pipe passage, and a flow rate controller configured to detect droplets in the refrigerant flowing through the pipe passage on the basis of a difference between detection values of the state detection sensors which are detected on the upstream and downstream sides of the resistance body, and controls a flow rate of the refrigerant on the basis of detection results.

A system for controlling or optimizing the performance of a vapor compression system by modifying the actuator commands via an output interface, that realizes thermofluid property functions and their derivatives as spline functions which are represented in a coordinate system that is aligned with a fluid saturation curve. The system includes an interface configured to receive measurement data from sensors, a memory configured to store thermofluid property data and computer-executable programs including a B-spline method, and a processor for performing the computer-implemented method. The processor is configured to take as input two thermofluid property variables, and compute a coordinate transformation in which one axis of the coordinates is aligned with the liquid and vapor saturation curves. In the saturation-curve aligned coordinates, a spline function represents the thermofluid property function, with coefficients and knots stored in memory. The spline function is constructed in a manner such that derivatives of the thermofluid property function may be discontinuous across the saturation curve.

A method for operating a refrigeration system for a motor vehicle. The method includes setting an operating mode of the refrigeration system having active primary line and inactive secondary line or having active secondary line and inactive primary line; detecting the pressure in the inactive line; and activating and extraction of refrigerant from the inactive line into the active line by lowering the pressure in the active line to a value below the pressure in the inactive line and by opening the relevant valve device.