The University of New England, Biddeford, ME

The existing chiller plant at the University of New England provided 350 tons of cooling to an infrastructure that will require 1,000 tons by 2007. The chiller plant building is nestled between other buildings and is surrounded by underground utilities and fiber optics cabling which made a simple expansion of the building impossible.

Johnson & Jordan, Inc. designed a chiller plant that would produce 1,000 tons of cooling

with increased efficiency, remain within the building footprint, and be completed in five months.

The existing chillers were relocated to make way for the first high-efficiency, 500-ton capacity chiller. By increasing the operating range, on the cooling towers (85F to 100F vs. 85F to 95F), only one additional cooling tower was required. The new tower, chilled water pumps, condenser water pumps, and associated piping were all sized and installed for the future replacement of the two older chillers with a second 500-ton chiller, which will increase the plant to 1,000 tons.

Temperature controls for the plant are DDC. System chilled water pumps have variable frequency drives and are controlled by pressure sensors. The campus building chilled water entrances were retrofitted with motorized control valves to vary the individual building flow rates and match the actual loads.

EQUIPMENT LIST

  • Trane Centri-Vac chiller
  • Canariis chilled water pumps
  • Taco condenser water pumps
  • ABB variable frequency drives
  • Marley cooling tower
  • Johnson Controls controls