HVAC
Part 1: Why HVAC Performance Gets Worse Over Time – By David P. Callan and Kyle Hendricks – January 2013
Part 2: Measures To Optimize HVAC Systems Include Energy Audits And Commissioning
Part 3: Utility Rebate Programs Can Help Fund HVAC Audits, Commissioning

“It’s sad but true. HVAC performance gets worse over time in almost all buildings.

HVAC systems in mid- to large-sized commercial buildings have increased in complexity steadily over the last 15 years. With the introduction of DDC controls and other building automation functions, even the most straightforward VAV systems are a compilation of components from multiple manufacturers, built by multiple contractors, that must be programmed and sequenced to work together seamlessly as intended.”

Read the full story at facilities.net including the reasons things go wrong.