AIR CONDITIONER AND METHOD OF OPERATING AN AIR CONDITIONER

An air conditioner and a method of operating an air conditioner are provided. The air conditioner may include at least one indoor device, each having an indoor heat exchanger installed therein; at least one outdoor device connected to the at least one indoor device by a refrigerant flow path, and each having a water-refrigerant heat exchanger that provides heat exchange between a refrigerant and heat source water and an outdoor device controller installed therein; a heat source water flow path connected to each water-refrigerant heat exchanger; a pump installed on the heat source water flow path; a variable flow valve installed on the heat source water flow path; a central controller that controls the at least one outdoor device; and a variable flow valve control board that regulates an opening degree of the variable flow valve and a flow rate of heat source water. The variable flow valve control board may be connected to the outdoor device controller via a first communication line, connected to the central controller via a second communication line having a different communication method from that of the first communication line, and perform protocol conversion between the central controller and the outdoor device controller.