HEATING AND COOLING EFFICIENCY IMPROVEMENT METHOD IN VEHICLE WITH CONTINUOUSLY VARIABLE VALVE TIMING-TYPE ENGINE FOR PROMOTING IMPROVEMENT OF HEATING AND COOLING PERFORMANCE THROUGH INCREASE OR DECREASE OF HEAT FLUX TO COOLANT

摘要

PURPOSE: A heating and cooling performance improvement method in a vehicle with a continuously variable valve timing-type engine is provided to improve the heating efficiency by increasing the heat flux to a coolant when the temperature of the coolant is low and to improve the cooling performance by decreasing the heat flux to the coolant when the temperature of the coolant is high. CONSTITUTION: A heating and cooling performance improvement method in a vehicle with a continuously variable valve timing-type engine comprises steps of starting the engine of the vehicle(S1); determining whether the temperature of a coolant sensed from a coolant temperature sensor is higher than preset minimum reference temperature and is lower than preset maximum reference temperature(S2); determining whether the temperature of the coolant is under the preset minimum reference temperature(S3); determining whether a heater switch is turned on(S4); increasing valve overlap to the utmost if the heater switch is turned on(S5); determining whether the temperature of the coolant is over the preset maximum reference temperature if the temperature of the coolant is higher than the preset minimum reference temperature(S6); decreasing valve overlap to a minimum if the temperature of the coolant is over the preset maximum reference temperature(S7); and normally controlling valve overlap on the basis of the valve timing optimally mapped in the fuel consumption ratio and exhaust gas suppression if the heater switch is turned off(S8).