Air-conditioning apparatus with switched connection states of windings of compressor motor prior to defrost operation

An air-conditioning apparatus comprising:

• a refrigerant circuit including a compressor, an indoor-side heat exchanger, and an outdoor-side heat exchanger, the compressor incorporating an electric motor;
• an inverter drive circuit configured to drive the electric motor;
• a connection switching relay device configured to switch connection of stator windings of the electric motor between a first connection state and a second connection state higher in line-to-line voltage than the first connection state;
• and
• a controller configured to perform heating operation, perform defrosting operation for removing frost formed on the outdoor-side heat exchanger and cause the connection switching relay device to switch connection, wherein
• when the controller causes the connection switching relay device to switch the connection of the stator windings from the second connection state to the first connection state during the heating operation, the controller
• first causes the connection switching relay device to switch the connection of the stator windings from the second connection state to the first connection state,
• then performs the defrosting operation even if a start condition of the defrosting operation is not met, and
• thereafter resumes the heating operation.