Succeeding in the competitive commercial real estate market in suburban Philadelphia is no problem for One Tower Bridge, a landmark 15-story office building located in West Conshohocken, near the bustling Schuylkill Expressway. But to keep its edge, building owners needed to replace the nearly 30-year-old HVAC units that supplied the facility's floor-by-floor variable-air-volume (VAV) system.
Each unit supplies conditioned air to terminal units, small metal boxes located in the supply air duct just before the outlet diffuser. The terminal units in One Tower Bridge use pressure-independent sensors that control a damper, which regulates maximum and minimum volumes of conditioned air supplied to the space.