Method for controlling air conditioner system

A method for controlling an air conditioner system which comprises one or more groups, each group comprising an outdoor unit and a plurality of indoor units, the method comprising:

• transmitting a channel switch request to the outdoor unit belonging to a particular group when a preset reception error rate occurs in one or more indoor units among the plurality of indoor units of the particular group;
• transmitting, by the outdoor unit, a channel scan command to each of the plurality of indoor units;
• performing a channel scan by the outdoor unit and each of the indoor units in the plurality of indoor units;
• transmitting, by each of the indoor units of the plurality of indoor units, results of the channel scan to the outdoor unit;
• determining, by the outdoor unit, a channel to be used among a plurality of channels by the particular group based on the result of the channel scan performed by the outdoor unit and the results of the channel scans received from the plurality of indoor units;
• and
• outputting, by the outdoor unit, information on the channel to the plurality of indoor units.