FIELD: control of operation of equipment in heating, ventilation and air-conditioning systems. SUBSTANCE: system determines whether people are present or not in room at any time and if people are present, system maintains temperature at preset User's point within permissible limits. In case there are no people in the room and temperature drifts beyond permissible limits, system permits temperature drift to maximum permissible limits or to limit determined anew which is lesser. Limit determined anew is based on determination of maximum temperature limit to which system may drift maintaining its ability to return temperature to User's point within preset maximum recovery time which is calculated on basis of previous temperature and time data stored for previous drift and control cycles. EFFECT: minimum power requirements; enhanced comfort, sanitation and other criteria. 47 cl, 12 dwg
