PURPOSE: To make it possible to obtain a temperature and a humidity having values same as predetermined ones at a desired place by a method wherein the temperature and humidity values detected by a temperature and humidity sensor are transmitted through ratio waves so as to enable a detecting place to be selected freely.

CONSTITUTION: The temperature and the humidity detected by the detector 4 are arranged in a transmission format and are and are inputted to a signal transmitter 8. Further, the waves modulated by the transmission format are transmitted by the transmitter 8 into the air as the radio waves through a transmission antenna 7. Next, the modulated waves received by a receiving antenna 6 are demodulated and transmitted to a temperature and humidity controller 2. The controller 2 is adopted to obtain a difference between the predetermined temperature set by a control panel 3 and the detected temperature and that between the predetermined humidity set by the control panel 3 and the detected humidity so as to control a cooler, a heater, a humidifying device and a dehumidifying device of the air conditioner 1, respectively.