Method for Controlling Vehicle HVAC System

An embodiment method for controlling a heating, ventilation, and air conditioning (HVAC) system of a vehicle includes determining a target subcooled temperature of a refrigerant based on a temperature and a pressure of the refrigerant discharged from an outlet of a compressor when the compressor operates, calculating a change in enthalpy of the refrigerant based on the determined target subcooled temperature in a process of condensing and subcooling the refrigerant, calculating a change in enthalpy of air passing over an exterior surface of a condenser based on the calculated refrigerant enthalpy change, and calculating a required fan duty of a cooling fan based on the calculated air enthalpy change, wherein the cooling fan is configured to blow the air to the condenser.