Air-conditioning apparatus including unit for increasing heating capacity

An air-conditioning apparatus including a check valve (CV1) that is provided in a passage between a first flow switching device (3) and a suction side of a compressor (1), a liquid piping expansion valve (LEV2) that is provided in midway of a liquid extension piping (20) and is capable of controlling a throughput of a refrigerant, an additional unit (300) having a first bypass (22a) and a second bypass (22b) that are branched off from a passage between an indoor unit (200) and the liquid expansion valve and are connected to a passage between the check valve and the suction side of the compressor, in which the first bypass has, in midway thereof, a first bypass expansion valve (LEVla) capable of controlling a throughput of refrigerant and an auxiliary heat exchanger (24) that has a heat source for heating different to the refrigerant, the auxiliary heat exchanger functioning as an evaporator heating the refrigerant flowing in the first bypass and in which the second bypass has, in midway thereof, a second bypass expansion valve (LEVlb) capable of controlling a throughput of refrigerant.