Belleville Clinic (Govt) | Dell Consulting LLC

Belleville Family Medicine Outpatient Clinic

Dell Consulting provided design for the HVAC, Plumbing, Electrical, and Communications systems for a complete Building Automation System (BAS) Upgrade. The design included network cabling, controllers, and BAS front end for over 258,000 SF of space throughout buildings 1529 and 1530. The project addressed aging mechanical and controls systems in an existing medical facility, while also improving energy efficiency, system monitoring, sustainability, and serviceability.

- Location: Scott AFB, IL
- Project Size: 258,000 SF
- Cost: $6,500,000
- Facility Type: Healthcare
- Owner: Air Force Medical Support Agency (AFMSA)
- Services: Electrical/Telecommunications and Mechanical/Plumbing Engineer

This project consisted of two parts – (1) provide a new building automation system (BAS) with direct digital controls (DDC) and (2) upgrade existing mechanical building systems. The BAS scope of work upgraded the building’s existing DDC system to a modern DDC system with BACnet communication and new actuators, sensors, control valves, control dampers, virtual points, and graphical user interface. All 40 existing variable frequency drives (VFDs), serving HVAC fans and pumps, were replaced with new VFDs in accordance with facility design standards and were integrated into the new DDC system. Approximately 20 central station air handling units (AHUs) and 360 variable air volume (VAV) terminal units were modified as part of the BAS scope of work. The three existing 350 ton water-cooled chillers in a N+1 configuration were entirely re-piped and headered so that any pump can pump through any chiller.

The electrical scope of work consisted of modifications to the existing electrical distribution system to support the new mechanical equipment. New mechanical panel panelboards were added in two of the facility penthouses to support new air handling equipment.

The mechanical systems upgrades included many sub-projects described as follows.

Existing steam-to-hot water heat exchangers were removed throughout the building. New heating hot water (HW) piping installed to provide a central steam-to-water heat exchanger station with variable-primary pumping system for the entire facility.
New HW preheat coils were retrofitted into 13 existing central station air handling units (AHUs).
A 100% outside air (OA) unit was converted to a mixed air unit with new return air ductwork, exhaust air ductwork, exhaust fan, return fan, and controls systems.
Existing 3-way control valves were replaced with 2-way valves to convert the chilled water (CHW) and HW systems to variable volume.
Four existing central station AHUs were removed and replaced with three AHUs equipped with HW preheat coils, CHW cooling coils, variable speed fans, and modern DDC systems consistent with the BAS upgrade.
The 5th floor of the building was converted from constant air volume to VAV with new supply and return air ductwork, new VAV terminal units, and HW piping.
Finally, the existing chilled water plant was converted to constant-primary, variable-secondary with a new primary CHW loop and primary CHW pumps; the existing secondary CHW pumps were rebalanced with new controls for automatic differential pressure control.