Air conditioner

An air conditioner comprising:

• an outdoor unit in which a refrigerant circulates;
• an indoor unit in which water circulates;
• a heat exchange device including a heat exchanger that is fluidly connected to the outdoor unit and to the indoor unit and performs heat exchange between the refrigerant and the water;
• a first outdoor unit connection pipe configured to connect the outdoor unit and the heat exchange device, the refrigerant flowing in a high-pressure gaseous state in the first outdoor unit connection pipe;
• a second outdoor unit connection pipe configured to connect the outdoor unit and the heat exchange device, the refrigerant flowing in a low-pressure gaseous state in the second outdoor unit connection pipe;
• a third outdoor unit connection pipe configured to connect the outdoor unit and the heat exchange device, the refrigerant flowing in a liquid state in the third outdoor unit connection pipe;
• a bypass pipe configured to communicate with the third outdoor unit connection pipe and the second outdoor unit connection pipe;
• and
• a bypass valve provided in the bypass pipe,
• wherein the heat exchange device includes:
• a first pipe connected to the first outdoor unit connection pipe;
• a first valve provided in the first pipe;
• a third pipe connected to the second outdoor unit connection pipe;
• a second valve provided in the third pipe;
• a refrigerant pipe connected to the third outdoor unit connection pipe;
• and
• an expansion valve provided in the refrigerant pipe, wherein the bypass pipe is connected to the second outdoor unit connection pipe or the third pipe.