Outside Air Dampers with Energy Recovery | Energy Efficiency
The dampers straight across are outside air dampers or make-up air coming from an energy recovery unit. According to the mechanical code, commercial buildings require a certain amount of fresh air from the outside to maintain good IAQ for the occupants.
An energy recovery unit allows it to be conditioned before being introduced into the building. Other methods include using enthalpy calculations to open economizer dampers and/or CO2 control of the dampers. (more…)
Rooftop Economizer CO2 | HVAC Control – This damper is part of a free cooling system for a rooftop economizer. It is part of an economizer damper system that allows free outside air cooling when the outside air temperature and humidity are ideal. This economizer also works on CO2 control so that if the CO2 levels inside the space rise above a set point the economizer damper opens allowing fresh outside air into the building while venting the air laden with CO2 to the outside. 
