AIR CONDITIONER AND ITS CONTROL METHOD

PROBLEM TO BE SOLVED: To provide a multiple type air conditioner and its control method capable of correctly determining cause of refrigerant shortage, and properly eliminating refrigerant shortage. SOLUTION: This multiple type air conditioner 1 comprises: a detecting means 2 for detecting temperature rise in a flow channel including a refrigerant pipe in which a refrigerant generated by refrigerant shortage or accumulation of refrigerant flows; an indoor unit side refrigerant returning means 3 performing the control to return the refrigerant accumulated at indoor units 30b, 30c, 30d side to an outdoor unit 20a in operation by operating the stopped indoor units 30b, 30c, 30d, when the detecting means 2 detects the temperature rise of the flow channel; an outdoor unit side refrigerant returning means 4 performing the control to return the refrigerant accumulated at the outdoor unit 20b side to the outdoor unit 20a in operation by operating the stopped outdoor unit 20b, when the detecting means 2 detects the temperature rise of the flow channel; and a determining means 5 for determining that the temperature rise of the flow channels is caused by the refrigerant shortage or accumulation of refrigerant on the basis of a result of the detection by the detecting means 2, after the control by the indoor unit side and/or outdoor unit side refrigerant returning means 3, 4 are executed. COPYRIGHT: (C)2010,JPO&INPIT