Air volume adjustment range depends on control method: VFD typically provides 20-100% of rated speed (and corresponding volume); damper control can reduce volume further but with energy penalty. Practical turndown is limited by fan stall region on the performance curve.
Air volume adjustment range depends on control method: VFD typically provides 20-100% of rated speed (and corresponding volume); damper control can reduce volume further but with energy penalty. Practical turndown is limited by fan stall region on the performance curve.