Variable Air Volume Systems – Commercial HVAC

by | Commercial HVAC | 1 comment

Variable Air Volume Systems - Variable Air Volume (VAV) systems are the best way to zone especially in large buildings. A VAV system with the proper controls and setup will help the building owner realize large savings in energy usage. There are many VAV systems out there set up in different ways. The most common set-up (for DDC) is, of course, usually the cheapest to install.

They have an air handler (DX or Chilled Water) which supplies the VAV Boxes with fixed pressure and temperature of the conditioned air. The VAV Boxes have electric reheat which will heat the air if that particular zone calls for heat (it is not uncommon to also find VAV boxes that have hot water reheat although this usually costs more to install but can save in energy costs). More on how VAV boxes work.

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Variable Speed Drives | HVAC Control

by | Direct Digital Controls | 0 comments

Variable Speed DrivesIn HVAC a variable speed drive is a speed control system for electric motors. The variable speed drive (VSD) or variable frequency drive (VFD), among other names (adjustable-frequency drives (AFD), AC drives, micro-drives, or inverter drives). The application of variable speed drives has brought about a new way of engineering buildings and control systems HVAC.

The flow of water and air can now be regulated precisely using VSD’s and state-of-the-art control systems. By combining VSD’s with state-of-the-art control systems, large savings in energy usage can see realization because the exact quantity of flow of water or air can be delivered to satisfy demand.

Demand-based control is energy efficient. VSD’s can be stand-alone or controlled by a building automation system.

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