Abstract: Means for air conditioning a building interior so as to afford optimum comfort to all its occupants in terms of their physical characteristics. An automatic control mechanism monitors devices for measuring humidity, air velocity, bulb temperature, and the weight and body temperature of humans or animals occupying the said interior. The mechanism comprises a calculator assembly comprising a computer and a comparator. Control is effected by comparing in the comparator the ideal temperature calculated by the computer with the actual measured temperature. The transmitted error signal imposes the control either on a heater or on a ventilator 1 in response to a command signal from a thermostat.