VORTEX ll®
Bi-Stable Vortex Fume Safety Cabinet

VFV Fume Hood Control Makes VAV Obsolete

Benefits

If you take a poorly performing fan with a badly designed fan wheel, and attach a high efficiency electric motor, variable speed drive, and a static pressure control, you would still have a poorly performing hood, but with very expensive controls. Unfortunately, when applying VAV control, whether open or closed loop, we are putting expensive controls on a poorly performing hood, and the results are the same as the fan, we still have a poorly performing hood.

The first fume hoods were fireplaces and they were used by alchemists. These alchemists did their work long before electricity, electric motors, fans or comfort engineers were invented. They first used candles and later gas burning rings in the stack to achieve the thermal lift required to make these fireplaces into fume hoods. Like its' cousin the fireplace, as the fume hood sash (hearth) opening is increased, the chamber size should also be changed to maintain the hood's maximum efficiency, but it was not. This fact makes all fume hood performance studies based only on face velocity irrelevant; since without the internal dimensional design of the tested hood, face velocity values become meaningless.

Once again, Flow Safe's engineers and ingenuity have not only solved the mystery of designing a mathematically correct fume hood to obtain maximum efficiency, but also created new technology for controls to enhance the fume hood's performance in it's environment.

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