Abstract: A single controller interface (Smart-Stat) integrates the control of heating or cooling in buildings by simultaneously controlling Heating, Ventilation and Air Conditioning (HVAC) systems in concert with separate fresh air ventilation (FAV) systems. The Smart-Stat reduces costs and the carbon footprint of typical HVAC systems by optimizing the use of FAV. User-programmable set-points are incorporated with time-of-day and day-of-week as well as data from multiple sensors, thermostats and weather information. Mathematical algorithms are used to determine control signals to the HVAC or FAV systems. The Smart-Stat integrates the two separate systems into a single system that is able to direct the call for cooling or heating to the HVAC or FAV systems, depending on appropriate outside weather conditions. Any building can replace its existing HVAC system controller with the Smart-Stat controller and incorporate a FAV system to create a single integrated HVAC and FAV system.

Abstract: The present invention is related to the field of heating, ventilation and air conditioning (HVAC). More particularly, the present invention is related to methods and systems for controlled heating and cooling in order to reduce costs and the carbon footprint of said heating and cooling by optimizing the use of fresh air ventilation. The present invention is directed to mathematical algorithms incorporated into a controller and a method of determining control signals that are dependent on said mathematical algorithms and user programming that integrates information from multiple sensors, thermostats as well as weather information. Used in any home or building, the controller controls heating, cooling and ventilation systems in order to reduce costs and the carbon footprint of said heating and cooling by optimizing the use of fresh air ventilation. The controller works with typical HVAC systems generally in buildings and homes.