US Patent 8356760 Apparent temperature controller

A HVAC control system is described that utilizes either a look-up table or an equation to calculate an apparent temperature based on the temperature and the moisture in the air at the control point. As the control system operates, the target temperature is constantly modified based on the current temperature and humidity or equivalently the calculated moisture in the air to maintain a constant apparent temperature. This has the effect of reducing the variance in the perceived comfort in the controlled area. An important additional feature is the cost savings due to reduced energy usage that is possible when external relative humidity conditions change so that less cooling or heating is required to maintain a comfortable environment.