A control device includes a shot-pulse control unit that provides, at a time of starting a synchronous motor, a predetermined current to each phase of a stator of the motor for a short time; a detecting unit that detects a current flowing through each phase when the predetermined current is provided; an estimating unit that estimates a position of the rotor by comparing detected values; a voltage control unit that controls application of a voltage to the synchronous motor based on a high-pressure side pressure of the compressor when the compressor is failed to be started due to any cause; and a magnetism-resistant section having a conductive layer sandwiched by insulating layers. The magnetism-resistant section covers a portion of a substrate of the control device, and a portion at which the conductive layer is exposed is in contact with the housing or a part conducting heat to the housing.