Air conditioner and method of operating an air conditioner

An air conditioner, comprising:

• at least one indoor device having an indoor heat exchanger that evaporates or condenses a refrigerant by heat exchange with indoor air;
• at least one outdoor device having a variable capacity compression device that sucks in and compresses a refrigerant from a refrigerant intake passage and discharges the refrigerant to a refrigerant discharge passage, a water-refrigerant heat exchanger that condenses or evaporates a refrigerant by heat exchange with heat source water, and an outdoor expansion device installed between the indoor heat exchanger of the at least one indoor device and the water-refrigerant heat exchanger;
• a heat source water flow path connected to the water-refrigerant heat exchanger;
• a pump installed on the heat source water flow path;
• and
• a variable flow valve installed on the heat source water flow path, wherein an opening degree of the variable flow valve is varied depending on at least one of a pressure of the refrigerant flowing from the variable capacity compression device to the water-refrigerant heat exchanger and a pressure of the refrigerant flowing from the water-refrigerant heat exchanger to the variable capacity compression device, and wherein, when the opening degree of the variable flow valve is varied, the opening degree is increased or decreased by a set amount.

A method of operating an air conditioner, the method comprising:

• opening a variable flow valve that regulates heat source water entering or exiting a water-refrigerant heat exchanger that provides heat exchange between a refrigerant and heat source water in a cooling operation of the air conditioner and in a heating operation of the air condition;
• and
• thereafter, in the cooling operation, increasing an opening degree of the variable flow valve if a pressure of the refrigerant flowing from a compression device that compresses the refrigerant to the water-refrigerant heat exchanger is higher than a target condensation pressure or decreasing the opening degree of the variable flow valve if the pressure of the refrigerant flowing from the compression device to the water-refrigerant heat exchanger is lower than the target condensation pressure;
• and
• in the heating operation, decreasing an opening degree of the variable flow valve if a pressure of the refrigerant flowing from the water-refrigerant heat exchanger to the compression device that compresses the refrigerant is higher than a target evaporation pressure or increasing the opening degree of the variable flow valve if a pressure of the refrigerant flowing from the water-refrigerant heat exchanger to the compression device is lower than the target evaporation pressure.