Fundamentals of

Retro-Commissioning

Tom MeyerCSME, GGP, CBCP, QCP, EBCP

The ESCO Group

Fundamentals of Retro-Commissioning

Fundamentals of Commissioning Existing Buildings

Fundamentals of Optimizing Existing Buildings

Purpose of Retro-Commissioning

Optimization of Existing Buildings

Why Existing Buildings?• Lots of existing buildings• All have opportunities • Benefits range from less

than a month to a year economic payback

• Helps identify capital and rehab projects with economic payback from one to 20 years.

Not ALL Buildings are Candidates

If there is no functional use and you want to save energy – close the building down.

Flavors of Commissioning

• New Construction Commissioning• Re-Commissioning• Continuous

Commissioning• Retro-

Commissioning

Defining Retro-Commissioning

Q: What does “retro-commissioning” mean?1. Returning out of spec equipment back to original

design.2. Commissioning a building again after several

years since it was commissioned as new construction.

3. Commissioning a building never before commissioned to the owner’s current requirements.

Limited in Scope

Most retro-commissioning programs are limited in scope. – System– Equipment– Problem

Motivation

The Building Owner’s motivation is the determining factor of scale and depth of the commissioning process.

Nuts and Bolts of Cx

• Benefits of Retro-Commissioning• Process of Retro-Commissioning• Commissioning Methods• Types of Commissioning

Top 10 Retro-Cx Measures

10. Improve boiler efficiency/controls 9. Reset supply static pressure setpoint 8. Review terminal unit operation 7. Return VFD to variable speed operation 6. Lower condenser water temperature

Courtesy of San Diego Energy Office

Top 10 Retro-Cx Measures

5. Calibrate sensors and instrumentation 4. System level and balance 3. Optimize economizer operation 2. Eliminate simultaneous heating & cooling 1. Turn off equipment when not needed

Courtesy of San Diego Energy Office

Confused?

Get Professional Help!

Any successful commissioning plan starts with the right people led by a person with the proper training and experience.

QUESTIONS?