| 摘要 |
PROBLEM TO BE SOLVED: To accurately start defrosting operation and improve the efficiency of heating operation by obtaining the temperature difference between a temperature of an indoor pipe of an air conditioner and a suction temperature after the lapse of a fixed time from the start of heating operation and after the lapse of a fixed time of heating operation, comparing the respective difference values with reference values and performing defrosting operation on the basis of judgement as to whether an outdoor heat exchanger may be frosted. SOLUTION: When a temperature TE2 of an indoor pipe of an air conditioner after the lapse of m2 minutes from the start of heating operation is higher than a temperature TE1 of the indoor pipe at the time of the lapse of m1 minutes from the start of heating operation, it is judged that an outdoor heat exchanger will not be frosted. Further, when the temperature TE2 of the indoor pipe after the lapse of m2 minutes from the start of heating operation is a fixed temperature or higher, normal heating operation is performed because there is little probability that the outdoor heat exchanger may be frosted. On the other hand, when the temperature of the indoor pipe after the lapse of m2 minutes from the start of heating operation is lower than the fixed temperature, the defrosting operation time is different according to the magnitude of Td = a temperature difference (TE1-TR1) at the time of the lapse of ml minutes}- a temperature difference (TE2-TR2) at the time of the lapse of m2 minutes}, wherein TR1 and TR2 each denotes a suction temperature at the time of each lapse of m1 minutes and m2 minutes, respectively. |
