A method for monitoring a refrigerant charge in a vapour compression system (1) is disclosed, the vapour compression system (1) including a compressor unit (2), a heat rejecting heat exchanger (3), a high pressure expansion device (4), a receiver (5), at least one expansion device (9, 10), and at least one evaporator (11, 12) arranged in a refrigerant path. A change in net mass flow into or out of the receiver (5) and/or a change in net enthalpy flow into or out of the receiver (5) is detected, and a pressure inside the receiver (5) is monitored as a function of time, following the detected change in net mass flow and/or in net enthalpy flow. A time constant being representative for dynamics of the receiver (5) is derived, based on the monitored pressure as a function of time, and information regarding a refrigerant charge in the vapour compression system (1) is derived, based on the derived time constant.

A climate-control system can be used to heat or cool a space. The climate-control system may include first and second vessels between which refrigerant and co-fluid may be circulated. The refrigerant may be absorbed into the co-fluid within the first vessel at a first rate. The refrigerant may desorb from the co-fluid within the second vessel at a second rate. Ultrasonic energy may be used to adjust the second rate to substantially match the first rate.

A refrigerant cycle device for a vehicle includes a compressor which compresses and discharges refrigerant, a discharge capacity control portion which controls a discharge capacity of the compressor. The refrigerant cycle device further includes a noise determination portion which determines whether an audible noise other than a refrigerant passing noise is in a low noise state, and/or a load determination portion which determines whether an air-conditioning thermal load is in a high load state. The discharge capacity control portion performs a gradual activation control in which the discharge capacity of the compressor is set to be lower than that determined in a normal control, when the noise determination portion determines that the audible noise is in the low noise state, and/or when the load determination portion determines that the air-conditioning thermal load is in the high load state, at an activation time of the compressor.

A refrigerating apparatus includes a centrifugal compressor, a capacity control mechanism that controls a capacity of the compressor by changing an opening degree of the capacity control mechanism, an expansion mechanism that reduces a pressure of a refrigerant, and a controller. The controller calculates an opening degree of the expansion mechanism using compressor capacity as one of a plurality of indices of change in load. The compressor capacity is obtained from a current rotation number of the compressor, an opening degree of the capacity control mechanism, and a divergence rate of a current operation head from a surge region.

An airstream cooling assembly includes an evaporator and a first and second condenser. The evaporator is configured to have a first airstream directed over its outer surface and to change the phase of a primary cooling medium from liquid to gas. The first condenser is configured to have a second airstream directed over its outer surface, transfer heat from the primary cooling medium, and change the phase of the primary cooling medium from gas to liquid. The second condenser is configured to accept a secondary cooling medium, and when accepting the secondary cooling medium, to receive the primary cooling medium from the evaporator, transfer heat from the primary cooling medium, and change the phase of the primary cooling medium from gas to liquid. The evaporator is configured to receive the primary cooling medium in the liquid phase from at least one of the first condenser and the second condenser.

A method for cooling air in an HVAC system includes moving refrigerant through a closed refrigeration circuit having, inter alia, an expansion device subsystem, which includes a full-load pathway and at least one partial-load pathway and a flow selector for directing refrigerant flow from the condenser to either the partial-load pathway or the full-load pathway. The method also involves directing refrigerant flow from the condenser to the full-load pathway when the refrigerant pressure is greater than or equal to a first preselected activation pressure and stepping down a refrigerant pressure with a set orifice and directing refrigerant flow from the condenser to the partial-load pathway when the refrigerant pressure is less than a second preselected activation pressure and stepping down a refrigerant pressure with a variable expansion device configured for partial loads. Refrigerant is delivered from the full-load pathway or partial-load pathway to the evaporator.

A control device and method for preventing the start and stop of heat source machines from being frequently repeated. The control device determining whether or not basic conditions for decreasing the number of machines are satisfied when the number of currently operating machines is increased by one is determined if a current operational status satisfies basic conditions for increasing the number of machines, and one heat source machine is started if it is determined that the basic conditions for decreasing the number of machines are not satisfied, and determining whether or not the basic conditions for increasing the number of machines are satisfied when the number of currently operating machines is decreased by one are satisfied if a current operational status satisfies the basic conditions for decreasing the number of machines, and one heat source machine is stopped if it is determined that the basic conditions for increasing the number of machines are not satisfied.

A refrigeration system includes a valve and a controller. The valve is configured to control the flow of refrigerant into an evaporator, the refrigerant having an associated liquid setting comprising a temperature and a pressure at which the refrigerant flows through the valve. The controller is operable to adjust the liquid setting, the adjusted liquid setting comprising a temperature and a pressure selected to improve energy efficiency under conditions currently being experienced by the refrigeration system, wherein the controller is operable to adjust the temperature and the pressure simultaneously such that the adjustment does not interfere with operation of the valve.

A refrigeration system includes at least one compressor, a condenser, one or more sensors, and a controller. The one or more sensors are operable to sense data associated with the refrigeration system. The controller is operable to receive operating data associated a first control variable and a second control variable, the operating data received from the one or more sensors. The controller is further operable to determine, based on the operating data, that a control objective is not met, and operate the refrigeration system according to a configuration selected to cause the control objective to be met in response to determining that the control objective is not being met, wherein operating the refrigeration system according to the configuration selected to cause the control objective to be met comprises overriding control of the second control variable until the control objective is met.

In an operation mode for heating battery air, a refrigerant passage switching portion switches over to a first refrigerant passage in which a refrigerant including gas refrigerant flowing out of an interior condenser flows into an auxiliary heat exchanger through a first pipe having a relatively large passage cross-sectional area and a liquid refrigerant flowing out of the auxiliary heat exchanger flows to an inlet of an exterior heat exchanger through a second pipe having a relatively small passage cross-sectional area. Meanwhile, in an operation mode for cooling the battery air, the refrigerant passage switching portion switches over to a second refrigerant passage in which a liquid refrigerant flowing out of the exterior heat exchanger flows into the auxiliary heat exchanger through the second pipe and a gas refrigerant flowing out of the auxiliary heat exchanger flows to a suction port of a compressor through the first pipe.