A system for predicting failure of a refrigeration unit includes a temperature measuring device placed within the refrigeration unit that has a temperature sensor in ambient air within the refrigeration unit to measure instantaneous temperature within the refrigeration unit. A transmitter within the refrigeration unit is operatively coupled to the temperature sensor to periodically transmit the instantaneous temperature. A receiver device located outside of the refrigeration unit receives the instantaneous temperature and records the instantaneous temperature over a time period to learn a refrigeration cycle of the refrigeration unit. After the receiver device learns the refrigeration cycle of the refrigeration unit, the receiver device measures a current refrigeration cycle of the refrigeration unit over a second period of time and when the current refrigeration cycle of the refrigeration unit over the second period of time differs from the refrigeration cycle of the refrigeration unit, the receiver device issues an alert.

An apparatus includes a flash tank, a first low side heat exchanger, a second low side heat exchanger, a first compressor, a second compressor, an expansion valve, a desuperheater, a sensor, and a controller. The first compressor compresses a refrigerant from the second low side heat exchanger. The desuperheater removes heat from the refrigerant from the first compressor. The second compressor compresses a mixture of the refrigerant from the first low side heat exchanger and the refrigerant from the first compressor. The expansion valve, actionable by the sensor and the controller, controls a flow of the refrigerant to the first low side heat exchanger such that the flow of refrigerant to the first low side heat exchanger is increased when a temperature of the mixture exceeds a threshold.

A refrigeration cycle apparatus in which a refrigerant having potential for disproportionation reaction circulates a first refrigerant flow path connected between a discharge side of the compressor and the condenser; a second refrigerant flow path connected between the condenser and the expansion valve; a third refrigerant flow path connected between the expansion valve and a suction side of the compressor; a jetting unit; a pressure measuring unit; and a temperature measuring unit. The jetting unit is configured to jet the refrigerant drawn from the second refrigerant flow path or the third refrigerant flow path to at least one of the compressor, the first refrigerant flow path and the second refrigerant flow path when at least one of a measured value of the pressure measuring unit and a measured value of the temperature measuring unit exceeds an allowed value.

A method for operating a coolant circuit of a vehicle cooling system in an AC mode and in a heating mode, implemented by a heat pump function, having an evaporator branch including an evaporator and a first expansion element, a coolant compressor, an AC and heat pump branch, having an outer condenser or gas cooler, as a heat pump evaporator having a second expansion element. The AC and heat pump branch is connected to the coolant compressor via a first blocking element and to the evaporator branch via the second expansion element, a heating branch having an inner heating condenser or heating gas cooler and a second blocking element, connected downstream thereto.

A driving apparatus includes: an inverter unit generating a three-phase alternating-current voltage from a direct-current voltage in accordance with a drive signal based on a voltage command and outputting the three-phase alternating-current voltage to a permanent-magnet motor, the permanent-magnet motor including a permanent magnet; a current detection unit detecting a motor current flowing through the permanent-magnet motor; and a control unit generating the voltage command to control an operation of the inverter unit and estimating a temperature of the permanent magnet to perform a protection operation on the inverter unit on the basis of the motor current and an overcurrent protection threshold. The control unit sets the overcurrent protection threshold on the basis of a magnet temperature estimated value of the permanent magnet and any one of a control computation period of the control unit, an output voltage frequency of the inverter unit, and a carrier frequency based on the output voltage frequency of the inverter unit.

As a refrigerant, a refrigerant containing a fluorocarbon having a property of causing a disproportionation reaction is used. A refrigeration apparatus includes: a refrigerant temperature detector configured to detect a discharged refrigerant temperature which is a temperature of the refrigerant that is being discharged from the compression mechanism or immediately after the discharge; and a controller configured to control the discharged refrigerant temperature detected by the refrigerant temperature detector such that the discharged refrigerant temperature is equal to or lower than a predetermined temperature Ts.

A fluid injection control system, a fluid injection control method and a fluid circulation system including the fluid injection control system are provided. The fluid injection control system includes an injection valve, control apparatus and energy storage apparatus. The injection valve is arranged in a path along which a fluid flows into a device; the energy storage apparatus is configured to supply, in response to the control apparatus being powered off, power to the control apparatus so as to maintain an operation of the control apparatus.

Provided is a vehicle air-conditioning apparatus heat pump system configured so that an excessive increase in the temperature (superheat degree) of refrigerant discharged from a compressor can be prevented in air-heating operation. The heat pump system (HP) includes a compressor (C) and an indoor heat exchanger (HXC2) on a refrigerant circuit (RC). A first branched flow path (BC1) on which a first expansion mechanism (EX1) of which opening degree is adjustable and a first heat absorption heat exchanger (HXA1) are arranged in series and a second branched flow path (BC2) on which a second expansion mechanism (EX2) of which opening degree is adjustable and a second heat absorption heat exchanger (HXA2) are arranged in series are arranged in parallel on the refrigerant circuit extending from the indoor heat exchanger to the compressor.

A method for controlling the temperature of a compressor having a motor including a rotor and a stator, and a control assembly operably coupled to the compressor, the method comprising the steps of: applying an initial current to the compressor motor; measuring a voltage across the compressor motor and determining a resistance of the compressor motor based on the initial current and a measured voltage; determining whether the determined resistance is less than or equal to a desired resistance; applying a secondary current to the compressor motor if the determined resistance is less than or equal to the desired resistance.

Systems and methods for operating a water recovery system and include activating a plurality of dampers, a fan, and a refrigeration system of the water recovery system. The method includes measuring an ambient air temperature of the water recovery system based on data obtained from an ambient air temperature sensor. The method includes measuring one or more evaporator temperatures associated with an evaporator of the water recovery system based on data obtained from one or more evaporator temperature sensors. The method includes determining an optimal evaporator air temperature of the water recovery system based on the one or more evaporator temperatures and the ambient air temperature. The method includes setting a speed of the fan of the water recovery system based on the optimal evaporator air temperature.