| 摘要 |
PROBLEM TO BE SOLVED: To improve EER and prevent frost from remaining by setting a defrosting time optimum. SOLUTION: When a defrost-in condition is established, an estimated defrosting time calculating unit 21 calculates an estimated defrosting time Tdef' using a frosting time Tfn-1 stored at the last time, a defrosting time Tdefn-1 at the last time and a frosting time Tfn at this time from a frosting time counting unit 27. A correction value setting unit 22 sets a correction valueαon the basis of an outdoor heat exchanger temperature Ten-1 stored at the last time of defrost-out. A defrosting time setting unit 23 corrects an estimated defrosting time Tdef' with the correction valueαto set the defrosting time Tfn at this time. In this manner, with reference to the frosting time Tfn-1 , defrosting time Tdefn-1 at the last time and an outdoor heat exchanger temperature Ten-1 at the time of defrost-out, a defrosting time Tdefn at this time is set so as to approach an ideal defrosting time, thus improving EER and preventing a remaining frost. |
