An electronically commutated asynchronous motor (12) features a stator (202), a short-circuit rotor (204), a controller (FOR 20) for field-oriented regulation of the motor (12), a sensor magnet (274) in thermally conductive connection with the short-circuit rotor (204), a rotor position sensor (14A; 18; 18′) arranged at a predetermined distance (d) from the sensor magnet (274) to generate an output signal (HALL, U, U1, U2) that is dependent upon the spatial orientation of the sensor magnet (274), and a temperature evaluation apparatus (CALC_T 44) configured to ascertain, during operation, from the sensor output signal (HALL, U, U1, U2), a temperature value (T) that characterizes a temperature (T_SM, T_S) in the motor (12).