A scheme of the HVAC system with local (zone) air handling units providing the possibility of heat and humidity treatment of air is developed to maintain the set temperature and relative humidity of the supply air. Features of regulation of moisture content of supply air in HVAC systems are considered and an analysis of air processing processes was carried out using the I-d diagram for the warm and cold periods of the year. A method for control the moisture content of the supply air is described, which allows more accurately to maintain the air parameters when the heat and humidity loads in the serviced rooms change.

Keywords: multizonal HVAC system, local (zone) air handling units, heat and moisture exchange, I-d-diagram, regulation of moisture content