The Powrmatic Thermal Economizer ATU’s can have outside air incorporated into the units. this could be for air quality concerns or just code required minimal air. Because the Thermal Economizer system has constant air flow, this means that we provide uninterrupted outside air when required. When the outside air is not required, the dampers are closed and the unit continues to heat the space without the expensive cost of heated outside air. Many systems have NO outside air options so more equipment will have to be installed to meet this demand. Which will have additional up front construction costs.
Then you have make up air units that use excessive amounts of outside air 24/7/365 and may not meet code outside air requirements due to the fans cycling on and off. Even when the facility has NO demand for outside air ( building unoccupied, limited or no process exhaust, etc. ), building owners are stuck paying for the high cost of heating outside air.