AIR CONDITIONER AND DEFROSTING DRIVING METHOD OF THE SAME

摘要

PURPOSE: An air conditioner and a defrosting method thereof are provided to increase the defrosting efficiency of an outdoor heat exchanger by changing the amount of refrigerant flowing to an outdoor heat exchanger performing a defrosting operation by decreasing the opening degree of an indoor expansion valve. CONSTITUTION: If a defrosting condition is satisfied, a defrosting valve is opened and a part of the refrigerant compressed by a compressor flows into an outdoor heat exchanger(S1). It is determined whether the temperature of the outdoor heat exchanger has reached a defrosting end temperature(S2). If not, the opening degree of the indoor expansion valve of the indoor heat exchanger is closed by a first predetermined degree(S3). It is determined whether the opening degree of the indoor expansion valve closed by the first predetermined degree has reached the minimum opening degree(S4). If yes, 'the opening of the indoor expand valve shut by the first setting ratio' arrives in to the minimum opening. It is determined whether the temperature of the outdoor heat exchanger has reached the defrosting end temperature(S5). If not, The temperature of the outdoor heat exchanger does not arrive in to the defrost extrication temperature. The defrosting valve is closed (S7).