Outside Air Optimization

Demand Control Ventilation, or DCV, uses CO₂ levels in the air to understand the occupancy and ventilation needs of each zone in a building, adjusting the ventilation rate in occupied spaces in an incremental way. This is based on either the return air CO₂, or a Trim and Respond system for zone-level DCV. Rather than ventilating all building spaces equally, the optimization of outside air comes from these preconfigured sequences which redirect air where it is needed for temperature or ventilation, reducing preventative and unplanned maintenace costs and reducing energy costs, all while measurably improving comfort and indoor air quality.

Bringing in outside air can often reduce expense by taking advantage of free cooling. Advanced economizer control takes into account weather forecasts, historical data, and a thermodynamic model of each customer building in the 75F Cloud to adjust outside air dampers in a coordinated way based on the enthalpy, or temperature and humidity of the air.

Comparative enthalpy economy from 75F uses real-time outside enthalpy data and constantly compares it with real-time indoor enthalpy data to lower energy costs and improve efficiency through free cooling. Not only does the system compare the two enthalpy values, it also calculates the final enthalpy of supply air when heated up to indoor levels using psychrometric logic to ensure the resulting air meets a desired target. The result consistently delivers three times more free cooling than a basic economizer with much better comfort for guests and occupants.