Backward Curve Fans

Backward Curve Exhaust Fan Design

We manufacture Backward Curve fans for a custom pneumatic system in Ontario. Our Backward Curve exhaust fan design meets the highest standards.

  • 4000 to 150 000 cfm
  • 18” to 98” wheel diameter
  • Up to 30” of water

The MacDonald Steel Backward Curve (BC) fan casing is manufactured from reinforced heavy plate construction.

The BC fan is a high efficiency exhauster, using 25% less power than conventional exhauster designs. The BC’s efficiency is derived mainly from its unique impeller. Its dimensions and backward curved blades have been purposefully designed to operate in the flow and pressure ranges required by dust collection systems.


The BC fan remains efficient over a wide range, making it insensitive to most system fluctuations or modifications. These combined factors often result in a smaller BC fan to do the same job.

Another advantage is the BC’s low sound levels. The casing and optional inlet box has been tuned to reduce sound levels by at least 29 dB versus other exhausters delivering the same performance.

Build a Blower for Cyclone Dust Collector

We can build a blower for cyclone dust collector systems.

Please contact us for more information on Backward Curve exhaust fan design and installing a custom pneumatic system in Ontario.