A refrigerant cycle apparatus includes a refrigerant circuit that circulates a refrigerant, and a leak sensor that detects a refrigerant leaking from the refrigerant circuit, in which the refrigerant cycle apparatus includes, as an operating mode, a recovery mode for recognizing occurrence of an abnormality in the leak sensor and recovering a refrigerant to a predetermined location in the refrigerant circuit.

A control method for an air conditioner comprising a compressor and an outdoor unit, wherein the control method includes: obtaining a suction temperature of the outdoor unit; and selectively adjusting the frequency of the compressor according to the suction temperature of the outdoor unit.

A method of operating a heat exchanger system in which a compressor, which is drivable by a motor, is fluidly interposed between an evaporator and a condenser following receipt of a shutdown command is provided. The method includes positioning inlet guide vanes (IGVs) of the compressor in a first position in the event of at least one of a first precondition being in effect and the first and a second precondition both not being in effect. The method further includes positioning the IGVs in a second position in an event the first precondition is not in effect but the second precondition is in effect, ramping a speed of the compressor down until a third precondition takes effect, removing power from the motor and positioning the IGVs in the first position once power is removed from the motor.

There is provided an absorption chiller including: a control unit configured to control opening and closing of the first control valve and an operation of the first pump, and a second supply flow path configured to supply the liquid inside the evaporator into the absorber; a second control valve opening and closing the second supply flow path; and a second pump configured to generate power to supply the liquid inside the evaporator into the absorber. After an operation of the absorption chiller is stopped, the control unit is configured to open the first control valve and operate the first pump such that a liquid inside the evaporator is mixed with the absorption liquid. Further, before the first control valve is opened and the first pump is operated, the control unit is configured to open the second control valve and operate the second pump.

A method for diluting a leaked refrigerant in a refrigeration system according to an example of the present disclosure includes operating the refrigeration system in a purge mode based on at least one purge condition prior to initiating a compressor of the refrigeration system. A refrigeration system according to an example of the present disclosure includes a compressor configured to compress refrigerant in a refrigerant line, a heat exchanger configured to exchange heat with the refrigerant line in a heat exchange mode, a fan configured to pass air through the heat exchanger to an indoor space, and a controller configured to operate the refrigeration system in a purge mode based on at least one purge condition prior to initiating the compressor.

A control device for a refrigerator system for cooling a load by using a plurality of refrigerators, said control device comprising a unit to control the number of operating units that changes the number of operating refrigerators according to the load rate, and a cold water temperature acquisition unit that acquires, via a temperature sensor, the temperature of cold water affected by the refrigerators. After a prescribed standby time from when the number of operating refrigerators was changed has elapsed, the unit to control the number of operating units changes the number of operating units and reduces the prescribed standby time when at least one of the cold-water temperature and the rate of change in the cold-water temperature satisfies a prescribed condition.

An illustrative example refrigerant system includes a compressor configured to pressurize a refrigerant fluid. The compressor includes a sump portion. A heater is situated to heat at least the sump portion. A controller is configured to selectively operate the heater to apply heat to at least the sump portion while the compressor is off to establish and maintain a superheat condition in the compressor.

A system includes a heat-pump circuit and a heating-fluid circuit. The heat-pump circuit includes a compressor and a first condenser conduit. The heating-fluid circuit includes first, second, and third flow-paths. The third flow-path selectively communicates with the first and second flow-paths. The first flow-path includes a first valve. The first valve moves between an open position allowing fluid flow through the first flow-path and a closed position restricting fluid flow through the first flow-path. The second flow-path includes a second condenser conduit and a second valve. When the second valve is open, fluid flows through the second flow-path. In the closed position, the second valve restricts fluid flow through the second flow-path. The third flow-path includes a heat exchanger receiving fluid from the first flow-path when the first valve is in the open position and receiving fluid from the second flow-path when the second valve is in the open position.

An air conditioning system including a compressor having a motor; a condenser; an evaporator; a drive providing multiphase, AC output to the motor; a motor braking assembly electrically connected to the drive, the motor braking assembly including at least one switch and at least one braking resistor; wherein the at least one switch is held in an open state by power from the drive; wherein upon disruption of power to the motor, the at least one switch assumes a closed state shorting windings of the motor through the at least one braking resistor.

A compressor includes a diffuser passage configured to receive refrigerant flow from an impeller of the compressor, where the diffuser passage is at least partially defined by a compressor discharge plate of the compressor. The compressor also includes a variable geometry diffuser positioned within the diffuser passage and configured to adjust a dimension of a refrigerant flow path through the diffuser passage, an actuator coupled to the variable geometry diffuser and configured to adjust a position of the variable geometry diffuser within the diffuser passage, and a controller configured to regulate operation of the actuator. The controller is configured to instruct the actuator to adjust the position of the variable geometry diffuser from a first position to a second position using a first force and to adjust the position of the variable geometry diffuser from the second position to a third position using a second force less than the first force, where the variable geometry diffuser abuts the compressor discharge plate in the third position.