A refrigeration system includes a startup mode control module that receives an off time of a compressor and an ambient temperature, determines whether the off time and the ambient temperature indicate that the compressor is in a flooded condition, and selects, based on the determination, between a normal startup mode and a flooded startup mode. A compressor control module operates the compressor in the normal startup mode in response to the startup mode control module selecting the normal startup mode, operates the compressor in the flooded startup mode in response to the startup mode control module selecting the flooded startup mode, and transitions from the flooded startup mode to the normal startup mode after a predetermined period associated with operating in the flooded startup mode.

A vehicle thermal management system including a refrigerant circuit, a coolant circuit, a chiller, and a controller is provided. The refrigerant circuit may include an electric air conditioning (eAC) compressor and a pressure sensor. The coolant circuit may include a high-voltage battery. The chiller selectively thermally links the circuits. The controller may be programmed to, responsive to receipt of a sensor signal indicating refrigerant pressure exiting the eAC compressor is greater than a high threshold, output a pressure sensor fault error indicating the pressure sensor is faulty. The system may further include a timer to monitor operational timing of the eAC compressor. The controller may be further programmed to direct the system to operate without monitoring the eAC compressor responsive to the timer indicating the eAC compressor has been off for a time-period less than a time threshold reflective of the eAC compressor not being in an at rest state.

A vehicle air conditioning system includes an in-vehicle air conditioner that includes a refrigerant circulation circuit including a compressor and an evaporator; a weather information acquiring section configured to acquire weather information at a current location of a vehicle; an evaporator drying determining section configured to estimate a water retention amount of the evaporator based on the weather information acquired by the weather information acquiring section and an operation state of the in-vehicle air conditioner, and to determine whether the evaporator is in a dry state; and a compressor stop permitting section configured to output a permission signal for permitting stop of the compressor on a condition that the evaporator drying determining section determines that the evaporator is in the dry state.

A system for controlling a compressor may include an engine controller controlling a fuel injection amount corresponding to an engine load and an opening amount of a throttle by reflecting a required torque required for an air conditioner, an operation information detector for detecting operation information according to driving state of the vehicle, a compressor generating pressure through a piston operation of a cylinder utilizing the power of the engine during operation of the air conditioner, and a controller determining an engine negative pressure of an intake manifold stored in the brake booster at a value, and when the negative pressure of intake manifold is below a first threshold value when the brake is operated, the engine enters a negative pressure recovery mode for predicting an insignificant negative pressure drop condition that falls below a second threshold value which is the A/C cut control condition and reduces the A/C duty.

There is disclosed a transport refrigeration system comprising an electronically governed engine that drives a refrigeration circuit of the system. The engine control unit is configured to operate the engine in a droop mode of operation, in which the engine speed increases with decreasing engine loads from the refrigeration circuit, so as to maximise the cooling capacity of the system at low engine load conditions.

A refrigerant loop of a vapor injection heat pump includes a compressor, first and second expansion valves, and first and second separator valves. The separator valves allow an entire refrigerant flow to pass therethrough or operate to separate vapor and liquid components of expanded refrigerant and inject the vapor component into a suction port of the compressor. Vapor injection occurs in both heating and cooling modes of operation and may depend upon an ambient condition (e.g., high or low ambient temperatures). An accumulator receives an output refrigerant of the heat exchangers dependent upon the mode and directs a vapor component into another suction port of the compressor. A control module controls at least the first and second expansion valves and first and second separator valves dependent upon the mode of operation which include, among others, heating, cooling, and dehumidification and re-heating.

A vehicle air conditioner is provided which is capable of detecting a refrigerant lack accompanying a refrigerant leakage and the like over time at the earliest possible stage and protecting a compressor. The vehicle air conditioner is provided with a compressor 2, a radiator 4, an outdoor expansion valve 6, and a heat absorber 9. The vehicle air conditioner holds normal time data indicating a relation between the number of revolutions NC of the compressor and a discharge refrigerant temperature Td thereof when a sufficient amount of refrigerant is filled in a refrigerant circuit R. The present invention calculates a discharge refrigerant temperature estimated value Tdst in normal time from the normal time data on the basis of a current number of revolutions NC and compares the discharge refrigerant temperature estimated value Tdst with a current discharge refrigerant temperature Td to determine a refrigerant lack of the refrigerant circuit.

An air conditioning system of a vehicle having an internal combustion engine includes a condenser configured to receive refrigerant output by an electric compressor and transfer heat from the refrigerant within the condenser to air passing the condenser. A first evaporator is configured to receive refrigerant from the condenser when a first control valve is open and transfer heat from air passing the first evaporator to the refrigerant within the first evaporator. A first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle. A second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and transfer heat from air passing the second evaporator to the refrigerant within the second evaporator. A second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle.

An air conditioning system of a vehicle having an internal combustion engine includes a condenser configured to receive refrigerant output by an electric compressor and transfer heat from the refrigerant within the condenser to air passing the condenser. A first evaporator is configured to receive refrigerant from the condenser when a first control valve is open and transfer heat from air passing the first evaporator to the refrigerant within the first evaporator. A first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle. A second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and transfer heat from air passing the second evaporator to the refrigerant within the second evaporator. A second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle.

Methods and systems for providing control of a heat pump of a motor vehicle are presented. In one operating mode, speed of a heat pump compressor is controlled responsive to an outlet pressure of the heat pump compressor. In a second operating mode, speed of the heat pump compressor is controlled responsive to a pressure ratio between an inlet and an outlet of the heat pump compressor.