Lab Air Conditioning

Project: Design/Build Office and Laboratory HVAC System
Project Value: $2.56 Million

Background: The facility consisted of four major buildings and a power plant housing boilers and chillers. The boilers, chillers and cooling tower were over 30 years old. The major consumer of high-pressure steam was a manufacturing facility, which was sold to another company five years prior.

Intent: The client asked BUIST to investigate the possibility of eliminating the boiler plant and installing a more economical chiller plant in the office and R&D facility. Such installation would eliminate the need for “around-the-clock” stationary engineering boiler supervision, and would allow substantial energy savings as a result of the smaller boilers and more efficient chillers.

Project Scope:

  • To site and install the new chillers and boilers
  • To separate and alter the steam requirements to create several low-pressure systems less than 100 HP.
  • To reduce energy consumption and assure a reasonable payback period. To design a system that could be maintained easily and economically.
  • To design a system that could be installed with a minimum impact on occupancy comfort.

The project included the following:

  • Space was created for the new chillers by adding a mezzanine in a high bay area; the area below was to be used for laboratories.
  • Two-stage, gas-fired absorption chillers were used to reduce the peak summertime energy use. The chillers were rigged into the building through openings in the roof, and the cooling towers were installed on the roof above the chillers.
  • The steam systems were separated into six (under 100 HP) low-pressure steam systems, and cast iron, sectional, gas-fired boilers were installed in the various buildings to replace the high-pressure steam system.
  • The existing steam piping from the power plant to the main building was converted for use for the gas distribution piping to the new chillers.
  • The existing chilled water zone pumps in those two buildings were changed to variable frequency drive pumps, and were de-coupled from the new chiller primary pumps to save energy.
  • The changeover from the old heating system to the new was accomplished by separately divorcing sections of the steam system, one at a time, and connecting each to a respective boiler.
  • The chiller changeover was accomplished by waiting until all steam systems were changed over, and the air conditioning season was over.


  • The project was completed on time and within budget
  • The project resulted in energy savings much greater than anticipated
  • The comfort of the occupants was greatly improved.
  • The client’s project manager, busy with other international projects, appreciated BUIST’s project management capabilities.
  • Permission to speak with the client may be arranged upon request, or BUISTS letter of reference may be reviewed upon request.