A 13-story office tower reduced its natural gas consumption by 65% and electricity consumption by 16% through adjusting direct digital controls, electrical measures and an innovative heat recovery system. The system features units that preheat entering fresh air and transfer the heat of warm water from fan-coil condensers into fresh air. Other improvements included installing condensing natural gas boilers, lighting fixtures, and adding variable speed drives to heating pumps and fans. This project was awarded first place for the 2009 ASHRAE Technology Awards.

Units: Dual