HVAC Analysis and Renovation Design

HVAC Analysis and Renovation Design - Horsham, PA


Beginning in 2011, GBA analyzed possible energy upgrades, focused on HVAC systems, for a four-building corporate campus totalling 390,000 square feet. The facility is devoted to technology development. The upgrade strategy ultimately consisted of custom air-cooled DX rooftop units, plus supplemental dry coolers to serve lab space.


Source Award
ASHRAE Illinois Chapter 2015 Excellence in Engineering Award


The buildings at this site were originally constructed as office space, but over time, about 40% of the property was migrated to research, straining cooling capacity. GBA developed multiple energy-saving HVAC options, including air-cooled, evaporative-cooled, and water-cooled strategies. Ultimately, custom air-cooled DX units were selected.

  • The custom air-cooled rooftop units displayed the best combination of front-end and life cycle costs for the client. Supply and relief fan arrays with VFDs were incorporated in the design, as well as variable-speed compressors, variable-speed condenser fans, and high-efficiency filters.
  • All RTUs feature direct digital controls tied into the campus’ existing building automation system.
  • Dry coolers were proposed and installed to better address current and future loads for the research spaces. 
  • Two buildings were upgraded between 2012 and 2104; upgrades are ongoing at other buildings. Replacements were done in phases so only half of each building was affected at any given time. In general, units were replaced over weekends.
  • The chart at the left shows representative electricity savings, using Building 2 as an illustration. Post-installation, Building 2 used 17% less electricity than the 2011 benchmark. Similar measurements at Building 3 indicated a 16% savings vs. the baseline measurements.
  • A subsequent retro-commissioning effort allowed the client to further improve energy efficiency at the site.