Demonstration of Tiered Trim and Respond Method  

Education Type: 
1 Hour
Professional Development Hours: 
1.0 PDH
Sponsored by: 

Environmental Security Technology Certification Program (ESTCP)


Tiered Trim and Respond (TTR) method is a version of the Trim and Respond (TR) method in resetting variable-air-volume air handling unit or rooftop unit supply air static pressure setpoint to save significant fan energy in partial load conditions. This session explains why supply air static pressure reset saves energy, compares the difference between TR and TTR, and then discusses an ESTCP field demonstration of implementing TTR at five DoD installations in detail. The five test sites use four different building automation systems to control their HVAC equipment. Fan energy saving results vary significantly and simple paybacks range from 1.7 years to 15 years. Lessons learned including factors influencing the effectiveness of the software-only control retrofit are summarized at the end.


Joe Zhou, Ph.D., PE, CEM, Slipstream

Learning Objectives

Upon completing this course, you will:

  • Introduce Tiered Trim and Respond (TTR) method​;
  • Describe TTR demonstrations at five DoD installations​;
  • Explain demonstration results​; and
  • Summarize factors impacting TTR implementation​
Federal Agencies and Facility Criteria: