| 摘要 |
PURPOSE:To stop defrosting operation when no frosting occurs by a method in which during the heating operation period, when the lowering degree of the temperature or pressure of vaporization and the integrating time until the temperature of vaporization becomes a constant value became constant or more, defrosting operation is started. CONSTITUTION:The variations in the temperature of vaporization for the case A where frosting occurs under fixed conditions of outdoor and indoor temperatures and the case B where no frosting occurs are shown in Fig. In the case of A, the temperature of vaporization falls with time because the function of the outdoor heat exchanger is lowered due to frosting. Then, the lowering degree of the temperature of vaporization per unit of time is detected, and when the lowering degree reaches a fixed value or more, the air conditioner is so controlled that defrosting operation is started. Or, the time taken for the temperature of vaporization to become a fixed value is integrated, and when the integrated time becomes a fixed time, defrosting operation is started. |
