Abstract: An improved, more efficient method of operation for a vehicle heating and air conditioning system electrically positions a temperature control actuator in accordance with a first temperature control schedule for coordinated control of compressor capacity and re-heating of the discharge air when air conditioning is enabled, in accordance with a second temperature control schedule when air conditioning is disabled. Both first and second temperature control schedules position the temperature control actuator as a function of the setting of the driver-manipulated temperature selector.

Abstract: An improved control method for a vehicle air conditioning system including a refrigerant compressor and a condenser cooling fan adjusts the power consumption of the condenser cooling fan in a manner to minimize the combined power consumption of compressor and the condenser cooling fan while maintaining adequate cooling of the condensed refrigerant. When the air conditioning system is operating at less than full capacity, the combined power consumption of the compressor and the condenser cooling fan is determined for each of a series of operating intervals. The change in the combined power consumption from one operating interval to the next is computed to determine the effect of a prior cooling fan power adjustment, and the power level of the cooling fan is incrementally adjusted in the same direction as the prior adjustment so long as the prior adjustment resulted in at least a specified reduction of the combined power consumption.

Abstract: An improved, more efficient method of operation for a vehicle heating and air conditioning system electrically positions a temperature control actuator in accordance with a first temperature control schedule for coordinated control of compressor capacity and re-heating of the discharge air when air conditioning is enabled, in accordance with a second temperature control schedule when air conditioning is disabled. Both first and second temperature control schedules position the temperature control actuator as a function of the setting of the driver-manipulated temperature selector.

Abstract: An improved method of operation for a vehicle air conditioning system controls an inlet air blower motor and an air inlet mixing device to reduce compressor and blower motor power consumption and achieve performance improvements associated with cabin air recirculation while maintaining a predefined level of outside air flow and a predetermined humidity level in the inlet air mixture of the system. The overall air flow is determined by the speed of the blower motor and the speed of the vehicle, and the speed of the blower motor and the position of the inlet air mixing device are adjusted as a function of both the vehicle speed and the selected blower motor speed so that the predefined level of outside air flow is preserved regardless of the vehicle speed and the selected blower motor speed.

Abstract: An improved method of operation for a vehicle air conditioning system controls an inlet air blower motor and an air inlet mixing device to reduce compressor and blower motor power consumption and achieve performance improvements associated with cabin air recirculation while maintaining a predefined level of outside air flow and a predetermined humidity level in the inlet air mixture of the system. The overall air flow is determined by the speed of the blower motor and the speed of the vehicle, and the speed of the blower motor and the position of the inlet air mixing device are adjusted as a function of both the vehicle speed and the selected blower motor speed so that the predefined level of outside air flow is preserved regardless of the vehicle speed and the selected blower motor speed.