| 摘要 |
[Problem] To provide an air conditioning device with which it is possible to prevent damage to a compressor and to prevent a delay in returning to a heating operation, by controlling the defrosting operation in accordance with the installation conditions. [Solution] The rotational frequency (Cr) of a compressor (21) during a defrosting operation is controlled with a control range that is in accordance with a capacity ratio (P), the total rated capacity (Pi) of the indoor units, or the refrigerant piping length (Lr). Thus, even when the amount of refrigerant circulation during the defrosting operation is reduced due to the installation state of the air conditioning device (1), it is possible to prevent the suction pressure from decreasing by a large amount and falling below a lower limit value for the capacity of the compressor (21). Accordingly, damage to the compressor (21) can be prevented. Furthermore, it is possible to prevent the execution of a low-pressure safeguard control when the suction pressure has fallen below the lower limit value for the capacity of the compressor (21). Therefore, there is no delay in returning to the heating operation due to a longer defrosting operation time, which occurs when the defrosting operation is interrupted by the low-pressure safeguard control. |
