Design 51 Double Width Fans

The Design 51 double width is a rugged fan built to Chicago's industrial level of quality and long-term dependability. Like every Chicago fan, the Design 51 is crafted by skilled members of the Sheet Metal Workers Union and displays the label "Proudly Made in the USA".


Design 51 identifies Chicago's series of hollow bladed airfoil centrifugal fans, acknowledged as the most efficient fan type for clean air applications. The double width configuration described boasts an enviable reputation for fan performance and reliability in a multitude of HVAC applications plus many industrial supply or exhaust systems.

Operating range

Maximum CFM 425,000
Maximum Static Pressure 20" wg
Maximum Temperature 150 degree Celcius
Fan Sizes 135 to 807


  • High efficiency hollow bladed wheel
  • Stable air flow over entire performance range
  • Substantially lower sound levels
  • Rigid bracing resists possible distortion from sudden airflow variations
  • Smooth steep pressure curve ideal for VAV systems
  • Spun steel wheel cone optimizes air flow
  • Continuously welded heavy steel construction
  • AMCA certified performance


  • Punched flanged outlet
  • Drain
  • Inlet volume control
  • Extended grease fittings
  • Continuously welded wheel
  • Mount motor and drive - A/3H
  • Outlet compainion flange
  • Access door
  • Inlet screen
  • Horizontal split housing
  • Optional bearings
  • Mounted belt guard - A/3H

Alternate Products

Greater CFM AF/BC Custom Heavy-Duty
Similar Products Design 10A Airfoil Centrifugal
  Design 51 Double Width


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