| 摘要 |
PURPOSE:To make it possible to detect the frosting of an outdoor side heat exchanger from the indoor side by detecting the temperature and power supply currents at the inlet portion and the central portion of a pipeline of an indoor heat exchanger. CONSTITUTION:Pipeline temperature detecting elements 6 and 6' are mounted on the coolant inlet side and the control portion of a pipeline of an indoor heat exchanger 3, respectively. A current detecting element 17 of an operation control portion detects a power source current. When a temperature difference DELTAt between an inlet pipeline temperature t1 and a central portion pipeline temperature t2 becomes less than a set pipeline temperature (t), it becomes necessary to defrost an outdoor side heat exchanger 5. However, a source current of the air conditioner reduces as compared with the case of a normal operation of the air conditioner. Accordingly, the absorbed coolant temperature Ts and the temperature difference DELTAt of a compressor 1 tend to rise and the power source current value (i) thereof tends to lower. Therefore, if a defrosting start judging condition is only a heat exchanger pipeline temperature difference value, the air conditioner does not start the defrosting operation even if the frosting proceeds. In this case, by properly setting the judgement point i1 of the power source current value (i), proper defrosting in a case where the coolant is short can be carried out.
|
