There is disclosed a vehicle air conditioner in which a refrigerant subcool degree of a radiator to satisfy both a high pressure and a refrigerant flow rate during heating can appropriately be controlled to achieve improvement of a heating capability. The vehicle air conditioner comprises a compressor 2 which compresses a refrigerant, a radiator 4 which lets the refrigerant radiate heat, an outdoor heat exchanger 7 disposed outside the vehicle interior to let the refrigerant radiate or absorb heat, and a controller. The controller executes a heating mode to let the refrigerant discharged from the compressor 2 radiate heat in the radiator 4, decompress the refrigerant by which heat has been radiated and then absorb heat in the outdoor heat exchanger 7. The controller 32 has a high pressure priority mode to increase a target radiator subcool degree TGSC of the radiator 4 in a direction in which the high pressure is set to a predetermined high value, and a revolution number priority mode to decrease the target radiator subcool degree of the radiator in a direction in which the revolution number of the compressor 2 is set to a predetermined high value.

Methods and systems are provided for adjusting a position of an air recirculation valve of a HVAC system to adjust a ratio of ambient to recirculated air routed to an AC evaporator to collect condensed water for water injection into an engine. In one example, a method may include adjusting the position of the air recirculation valve of the HVAC system based on a water level in a water storage tank of the water injection system. Further, the method may include adjusting the position of the air recirculation valve of the HVAC system based on a determined humidity of the ambient air and a determined humidity of the recirculated air.

An air conditioning control system which is provided in a vehicle includes an air conditioning device and a controller. The controller is configured to acquire vehicle outside humidity information representing humidity when a start switch of the vehicle is turned on, execute outside air introduction processing for making an outside air introduction ratio of the air conditioning device greater than 0% in an off state of the start switch, and when a first condition that the outside air introduction processing is executed is satisfied, calculate vehicle inside absolute humidity of the vehicle in an on state of the start switch with absolute humidity based on the acquired vehicle outside humidity information as an initial value.

An air conditioning and refrigeration system for a container equipped with a transport refrigeration unit (TRU) is disclosed. The system comprises a variable speed fan configured with the TRU, and one or more first sensors positioned at predefined positions at a rear section of a conservation space associated with the container. The one or more first sensors are configured to monitor one or more first attributes associated with the rear section. The system further comprises a controller in communication with the one or more first sensors and the fan. The controller is configured to adjust speed of the fan and/or adjust cooling capacity of the TRU based on the monitored first attributes of the rear section, to maintain a predefined environment at the rear section or across the conservation space.

There is disclosed a vehicle air conditioner which is capable of enlarging an effective range of a dehumidifying and heating mode to environmental conditions and smoothly dehumidifying and heating a vehicle interior. A vehicle air conditioner 1 executes a dehumidifying and heating mode in which a controller lets a refrigerant discharged from a compressor 2 radiate heat in a radiator 4, and decompresses the refrigerant by which heat has been radiated and then lets the refrigerant absorb heat in a heat absorber 9 and an outdoor heat exchanger 7, the controller decreases an outdoor blower voltage FANVout of an outdoor blower 15 and decreases an air volume into the outdoor blower 15 in a case where a temperature Te of the heat absorber 9 is high even when the controller adjusts a valve position of an outdoor expansion valve 6 into a lower limit of controlling in a situation in which a temperature TCI of the radiator 4 is satisfactory.

An air conditioner for a vehicle includes a casing, a cooling heat exchanger, a cooling temperature adjusting portion, a dew-point detector, a target temperature determining portion, and a cooling temperature control portion. The cooling heat exchanger is arranged in the casing to cool air to be blown into a vehicle compartment. The cooling temperature adjusting portion adjusts a cooling temperature of air cooled at the cooling heat exchanger such that the cooling temperature approaches a target cooling temperature of the cooling heat exchanger. The dew-point detector detects a dew-point temperature of air flowing to the cooling heat exchanger. The target temperature determining portion determines the target cooling temperature to be a first target temperature lower than the dew-point temperature by a standard degree, and temporarily to be a second target temperature lower than the first target temperature.

A vapor compression cooling system includes a centrifugal compressor(s) for compressing a primary fluid in a cycle including at least two compressions, and a control module for controlling the centrifugal compressor dependent upon at least a condition of a secondary fluid. The module controls a power of the centrifugal compressor by adjusting a speed of the motor driving the compressor and/or an opening of guide vanes associated with at least one impeller. The module may also control a pressure drop of a primary fluid moving through at least one expansion device. The at least two compressions may be made in parallel or in series. A related method includes compressing a primary fluid in a first and a second compression cycle and adjusting a parameter of the compressor dependent upon a calculated desired power of the compressor.

A refrigeration efficiency monitoring system detects degradation of a refrigeration system by monitoring a deviation from a normal operating status of the refrigeration system at an early stage of such degradation. The monitoring system detects and calculates a plurality of system parameters associated with the refrigeration system. The monitoring system then determines a decrease in efficiency of the refrigeration system based on comparison between the system parameters and reference values representative of the normal operating status, and generate a service recommendation based on the determination.

A vehicle climate control system has a control strategy which controls temperature of an evaporator in a refrigeration circuit to achieve a target temperature/relative humidity within a comfort zone which is defined by upper and lower temperature boundaries and upper and lower relative humidity boundaries. Several system embodiments are disclosed, including an all-electric system. All systems operate with improved efficiency.

A dehumidification mode control method and apparatus, a device, a medium and a program product, implemented by means of: obtaining a dehumidification load of a heat pump system and an external ambient temperature when it is detected that a passenger compartment has a dehumidification demand; determining whether to enter a first dehumidification mode according to the dehumidification load, the external ambient temperature and a load threshold; if yes, then determining a control instruction of the first dehumidification mode according to an air temperature at multiple first preset positions in an air transmission heat exchange box and a subcooling degree of a heat exchange medium at at least one second preset position in a transmission pipeline; and then outputting the control instruction so that a first target temperature and a second target temperature simultaneously meet a preset requirement of a dehumidification function.