One Rotary Center is the worldwide headquarters of Rotary International; the 18-story building was erected in 1977.
- Two existing 520-ton chillers using R-11 refrigerant were replaced with two new chillers using R-123 refrigerant.
- The existing chillers were rated at 0.8 kW/ton, compared with the replacement chillers at full load ratings of 0.56 kW/ton and an NPLV of 0.47 kW/ton. Both replacement chillers are equipped with variable-frequency drives.
- The chilled water distribution system was converted from constant flow to variable-primary flow.
- System modifications simplified the piping system and reduced the number of pumps used by two.
- Chillers were pre-ordered and pre-selected by the owner based on life cycle cost analysis.
- The project included a mechanical room refrigerant leak detection system, ventilation, and purge exhaust required to meet ASHRAE Standard 15 requirements.
- ComEd, the local electrical utility, provided an incentive of $60,000, based on the efficiency of the new chillers.
