Patent ID: 8770492

Claim:
A controlling method of an air conditioner, the method comprising: receiving an externally input temperature; determining an initial operation temperature based on the received externally input temperature or a preset program temperature; cooling or heating a designated space at the determined initial operation temperature for an initial operation time period; and after the initial operation time period has elapsed, cooling or heating the designated space to a comfort temperature, wherein the externally input temperature is a temperature between the initial operation temperature and the comfort temperature in both a cooling operation and a heating operation of the air conditioner, wherein cooling or heating the designated space to a comfort temperature comprises incrementally increasing or decreasing a room temperature to the comfort temperature, comprising: increasing or decreasing a current temperature by a preset temperature interval and re-setting the current temperature accordingly; cooling or heating the designated space at the re-set current temperature for a preset time interval, including increasing the preset time interval each time the current temperature is increased or decreased such that a current time interval is greater than a previous time interval; and repeating the increasing or decreasing and the cooling or heating steps until the room temperature reaches the comfort temperature.