Patent attributes
An air-conditioning apparatus control system includes connected devices each including a memory to sequentially store control data which is acquired during operation and is associated with control of the connected device. To back up the control data in the memory of the connected device, a backup destination is selected from the other connected devices included in a plurality of air-conditioning apparatuses constituting the air-conditioning apparatus control system on the basis of an available memory space in each of the other connected devices. The control data is backed up to the selected backup destination at time when it is determined that backup has no interference with communication for a normal operation in the air-conditioning apparatus control system.