A receiver unit includes: a receiving section receiving a signal of a measurement value (Tm2) transmitted from a wireless temperature sensor unit; an input connector connected to a sensor signal line, the sensor signal line being configured to transfer a signal of a measurement value (Tm1) of the suction air temperature sensor; a signal generator generating a signal serving as an index of indoor temperature, based on the measurement values (Tm1, Tm2) of the wireless temperature sensor unit and the suction air temperature sensor; and a signal output section outputting the signal generated by the signal generator to a controller of an air-conditioning device.