Heat pump with simultaneous cooling and defrosting of heat exchangers arranged in parallel

An air conditioner, comprising:

• an outdoor unit comprising a compressor that compresses a refrigerant, and an outdoor heat exchanger that performs heat-exchange between outdoor air and the refrigerant;
• an indoor unit comprising a plurality of indoor heat exchangers that performs heat-exchange between indoor air and the refrigerant, and a plurality of indoor expansion valves which is connected to the plurality of indoor heat exchangers and expands the refrigerant;
• and
• a continuous refrigeration apparatus permitting cooling to continue with at least one of the plurality of indoor heat exchangers providing cooling, while at least one other of the plurality of indoor heat exchangers is undergoing defrosting, the continuous refrigeration apparatus comprising a first gas control unit connected to a first indoor heat exchanger of the plurality of indoor heat exchangers, a second gas control unit connected to a second indoor heat exchanger of the plurality of indoor heat exchangers, a first pipe that connects a liquid pipe of the outdoor unit and a liquid pipe of the indoor unit, and a second pipe which is branched from the first pipe and connected to the first gas control unit and the second gas control unit, wherein the first gas control unit comprises:
• a first-first flow path that connects the first gas control unit to the second pipe;
• a first-second flow path which is connected to the first-first flow path, and through which the refrigerant discharged from the first indoor heat exchanger flows during a refrigeration operation of the first indoor heat exchanger;
• a first-third flow path which is connected in parallel with the first-second flow path, and guides the refrigerant discharged from the compressor to the first indoor heat exchanger during a defrosting operation of the first indoor heat exchanger;
• a first-first solenoid valve which is installed in the first-first flow path, and controls a flow of the refrigerant flowing through the first-first flow path;
• a first-second solenoid valve which is installed in the first-third flow path, and controls a flow of the refrigerant flowing through the first-third flow path;
• a first-first check valve which is installed in the first-second flow path, and blocks a flow, toward the first-first flow path and the first-second flow path, of the refrigerant introduced into the first gas control unit from the gas pipe of the outdoor unit, and guides the refrigerant toward the first-third flow path;
• and
• a first-second check valve which is installed in the first-third flow path, and blocks a flow of the refrigerant, which is introduced into the first gas control unit from the first indoor heat exchanger, flowing through the first-third flow path, and guides the refrigerant toward the first-second flow path, and connects a gas pipe of the outdoor unit and the first indoor heat exchanger, wherein the second gas control unit comprises:
• a second-first flow path that connects the second gas control unit to the second pipe;
• a second-second flow path which is connected to the second-first flow path, and through which the refrigerant discharged from the second indoor heat exchanger flows during a refrigeration operation of the second indoor heat exchanger;
• a second-third flow path which is connected in parallel with the second-second flow path, and guides the refrigerant discharged from the compressor to the second indoor heat exchanger during a defrosting operation of the second indoor heat exchanger;
• a second-first solenoid valve which is installed in the second-first flow path, and controls a flow of the refrigerant flowing through the second-first flow path;
• a second-second solenoid valve which is installed in the second-third flow path, and controls a flow of the refrigerant flowing through the second-third flow path;
• a second-first check valve which is installed in the second-second flow path, and blocks a flow, toward the second-first flow path and the second-second flow path, of the refrigerant introduced into the second gas control unit from the gas pipe of the outdoor unit, and guides the refrigerant toward the second-third flow path;
• and
• a second-second check valve which is installed in the second-third flow path, and blocks a flow of the refrigerant, which is introduced into the second gas control unit from the second indoor heat exchanger, flowing through the second-third flow path, and guides the refrigerant toward the second-second flow path, and connects the gas pipe of the outdoor unit and the second indoor heat exchanger.