A server is provided. The server includes a communicator and a processor configured to receive driving information of a plurality air conditioning devices through the communicator, identify an opening and closing cycle of a valve included in a pipe connected to each indoor unit of the plurality of air conditioning devices to control flow of a refrigerant, based on the driving information, group each indoor unit of the plurality of air conditioning devices into a plurality of groups based on the opening and closing cycle of the valve, based on a power consumed by the plurality of the air conditioning devices reaching a reference power amount, identify at least one group among the plurality of groups based on information about a control priority, and transmit a signal for driving control to at least one indoor unit included in the at least one group through the communicator.