Air-conditioning apparatus

An air-conditioning apparatus comprising:

• a refrigerant circuit in which a compressor, a heat source side heat exchanger, an expansion valve, and a use side heat exchanger are connected by pipes that circulate refrigerant;
• a first on-off valve provided at a pipe between the expansion valve and the use side heat exchanger;
• a bypass branching from a pipe between the expansion valve and the first on-off valve and connected to a pipe on a suction side of the compressor;
• a second expansion valve provided at the bypass;
• a refrigerant storage unit configured to store the refrigerant passed through the bypass;
• and
• a controller configured to operate the compressor and to perform a pump down operation in which the refrigerant is stored in the refrigerant storage unit,
• wherein the refrigerant storage unit comprises an accumulator provided on the suction side of the compressor,
• the bypass is connected to a pipe between an inflow side of the accumulator and the use side heat exchanger,
• the controller performing the pump down operation controls the first on-off valve to be in a closed state so that the refrigerant flowing into the bypass from the heat source side heat exchanger is stored in the refrigerant storage unit, and
• in the pump down operation,
• the refrigerant flowing into the bypass is expanded by the second expansion valve, and then, flows into the accumulator, and
• the refrigerant flowing into the accumulator is stored.