Central Chiller Plant Modernization

Project overview

Sage Engineering Associates, LLP provided mechanical, electrical, structural coordination, and controls engineering services for the modernization of the Bassett Medical Center central utility plant serving the hospital campus. The multi-phase project upgraded the facility’s chilled water generation and heat rejection systems to improve reliability, operational efficiency, redundancy, and plant performance while maintaining continuous operation of the active healthcare campus.

The project included the replacement of three cooling towers and one central chilled water plant chiller, along with major upgrades to the condenser water, chilled water, and plant control systems. Work included installation of a new high-efficiency magnetic bearing centrifugal chiller, replacement cooling towers with variable frequency drive fan control, new condenser water and chilled water pumping modifications, structural support upgrades, vibration isolation systems, condenser water piping modifications, heat tracing systems, and BAS/DDC integration.

Sage Engineering developed new chiller plant operating sequences designed to optimize plant efficiency and respond dynamically to varying campus cooling loads. The upgraded control system integrated the new magnetic bearing chiller with the existing Johnson Controls campus control system and included system flow meters, BTU/energy metering, condenser water temperature monitoring, chiller staging logic, pump sequencing, and cooling tower optimization strategies. The new sequences allow the plant to automatically adjust equipment operation based on building cooling demand, improving energy performance and operational reliability across the medical campus.

The cooling tower replacement work included new stainless steel crossflow cooling towers, vibration isolation systems, basin heaters, heat trace systems, liquid level controls, maintenance access platforms, and associated structural steel support modifications. The project also included electrical infrastructure upgrades for new equipment, VFDs, controls, power distribution modifications, and instrumentation required for advanced plant monitoring and operation.

Construction was carefully phased and coordinated to maintain uninterrupted chilled water service to the active hospital campus throughout the duration of the project.