When Urban Renaissance Group purchased Tower 333, a 20-story office building in Bellevue, Wash., they knew the aging and inefficient water-booster system needed to be replaced. The original system consisted of three 20-horsepower constant-speed booster pumps operated in a staged sequence, bringing on successive pumps as demand changed. With a commitment to occupant comfort and maintaining the building's energy-efficiency certifications, the company knew they had to find a replacement for the aging water-booster system that would save energy and improve performance.