This project was a design build solution by Powers that transformed a poorly operating HVAC system into an efficient system that also increased the occupant comfort level. The DX AHU was leaking and inefficient. The VAV boxes were poorly zoned and not controlling properly due to outdated pneumatics and lack of volume control.
We had CLEAResult perform an energy profile on the original system and the building was performing so badly that the readings were outside their parameters to properly model the performance. In addition to being inefficient the system was not providing the comfort level that the occupants require.
We were able to utilize the existing equipment stands to set the new chillers. We set the chillers in phases and replaced the DX coil with a chilled water coil once a couple of the chillers where ready to go. This plan meant that we did not leave the building without cooling while it was occupied. We utilized variable primary pumping to maximize pump energy savings.
Powers replaced the fans and provided VFD’s for all 12 fan modules in the fan wall. We provided backdraft dampers for each module as well. By providing VFD’s for each module, the system became more reliable than the existing two system, meaning, one fan failure will never reduce the system capacity below 90%.
We replaced the VAV boxes and installed new Siemens digital controls with minimal occupant disruption. We programed the system to use all available energy savings tactics by providing temperature and static resets at the AHU level. We also programed setbacks and Occ/unocc schedules at the VAV level. By providing digital controls, we were able to limit user temp setpoints at the thermostats.
Once the project was completed, CLEAResult measured the performance of the system and provided a rebate to the building owner based on the efficiency gains. The building is not only more efficient but is providing a more comfortable space for the occupants.