You are operating a 2,000 ton steam-driven turbine centrifugal system providing 46 F chilled water; one building is unsatisfied. What action should you take?

• A. Shut down the system
• B. Put an additional chilled water pump online
• C. Increase water temperature
• D. Close valves to that building

Answer: (B)

Increasing the flow to the underserviced building is the right move. In a chilled-water system, the amount of cooling a building gets depends on how much water is circulated through its cooling coil and the water temperature leaving the chiller. Since the system is delivering 46°F water, the temperature is fixed; the only way to remove more heat for the building is to move more water through its coil. Adding another chilled water pump in parallel raises the total flow to that building’s loop, delivering more cooling without changing the leaving water temperature.

Shutting down the system would cut cooling to every building, not just the one in need. Raising the supply temperature would reduce the amount of heat you can remove at the same flow, making the problem worse for that building. Closing valves to the building would prevent cooling altogether. So bringing an additional pump online directly addresses the imbalance by increasing capacity where it’s needed.