Reaping the benefits of optimized control
VAV systems with optimized controls can often deliver an annual energy savings of between 10 and 20 percent, when compared to a traditional VAV system control.
Upgrading a VAV system to use optimized controls
In addition to helping building owners save fan energy, optimized VAV system controls can save cooling and heating energy by optimizing when the system starts up or shuts down each day, resetting the supply-air temperature setpoint, and optimizing ventilation through the use of demand-controlled ventilation.
For building owners, choosing to upgrade an older VAV system to implement these optimized control strategies doesn’t have to mean replacing the entire system, which could be costly and disruptive to building occupants. Rather, it’s possible to retrofit an existing system by installing retrofit dampers in the ducts leading to the older VAV terminals.
Some available retrofit dampers already have all the communicating controls required to implement these optimized control strategies. In addition, wireless zone sensors and wireless communications between the VAV controllers and BAS simplify the upgrade by avoiding the need to pull communication wiring, allowing for easier relocation when space layout or use changes in the future.
Upgrading an older VAV system to an intelligent VAV system with optimized controls not only saves energy, but allows the building operator to verify system energy savings over time, identify and correct problems, and more easily make changes in the future. And with retrofit dampers and wireless controls, upgrading has never been easier.
John Murphy is an applications engineer who has been with Trane since 1993. Murphy is the author of numerous Trane application manuals and Engineers Newsletters, and is a frequent presenter on Trane’s Engineers Newsletter Live series. He is a member of ASHRAE, has authored several articles for the ASHRAE Journal, and has presented on a national ASHRAE webcast. He was also a member of several of the committees responsible for ASHRAE’s Advanced Energy Design Guides.
Slideshow photo by icedsoul photography.