| 摘要 |
PROBLEM TO BE SOLVED: To provide an air conditioner capable of limiting frost formation of an outdoor heat exchanger only on a refrigerant inlet side, reducing frequency of defrosting and completing defrosting for a short time.SOLUTION: In the air conditioner 1, a refrigerant compressor 2, a four-way valve 3, an indoor heat exchanger 4, an expansion device 5 and the outdoor heat exchanger 6 are communicated by refrigerant piping 7, and zeotropic refrigerant mixture is used as a refrigerant. Control is performed so that the refrigerant made to flow out from the outdoor heat exchanger 6 and sucked to the refrigerant compressor 2 is heated by a heater 9 when a value indicating a frost formation state of the outdoor heat exchanger 6 sensed by a frost formation sensing part 8 during heating operation exceeds a predetermined value and so that heating by the heater 9 is stopped and part of the refrigerant made to flow out from the refrigerant compressor 2 is made to flow in from the refrigerant inlet side of the outdoor heat exchanger 6 through a bypass passage 11 when the suction temperature of the refrigerant sucked to the refrigerant compressor 2 becomes a predetermined temperature or lower or when the value indicating the frost formation state of the outdoor heat exchanger 6 sensed by the frost formation sensing part 8 exceeds a second predetermined value. |
