<p>An object is to provide an air-conditioning apparatus in which the coolant can be preheated without causing vibrations or noise. The air-conditioning apparatus includes a coolant circuit configured by sequentially connecting a compressor 1, an indoor heat exchanger 5, an expansion valve 4, and an outdoor heat exchanger 3; a motor 12 that operates a compressor mechanism 11 disposed inside the compressor 1; an inverter 6 for driving the motor 12; and a control unit 7 that controls the inverter 6. The control unit 7 includes a liquefaction detecting unit 74 that detects coolant liquefaction in the compressor 1; includes a first PWM signal generating unit 72 that generates an inverter control signal for driving the motor 12; includes a second PWM signal generating unit 73 that generates an inverter control signal for making the motor 12 perform a preheating operation; and includes a switching unit 71 that performs switching in such a way that the first PWM signal generating unit 72 or the second PWM signal generating unit 73 outputs the corresponding inverter control signal to the inverter 6.</p>
