| Centrifugal & Inline Fan & BLOWER Types |
| Diagram |
Description |
Applications |
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Forward Curved
The wheel's blades are small and curved forward in the direction of the wheel's rotation. This fan runs at a relatively low speed to move a given amount of air. This wheel type is most often called a squirrel cage wheel. |
Primarily for low pressure heating, ventilating and air conditioning such as domestic furnaces, central station units and packaged air conditioning equipment. |
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Radial Blade
This wheel is like a paddle wheel… with or without side rims. The blades are perpendicular to the direction of the wheel's rotation andthe fan runs at a relatively medium speed to move a given amount of air. |
The radial blade type is designed for material handling applications, features rugged construction and simple field repair. Also used for high pressure industrial requirements. |
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Backward Inclined
The wheel's blades are flat and lean away from the direction of the wheel's rotation. This fan runs at a relatively high speed to move a given amount of air. It is more efficient than the above listed types. |
General heating, ventilating and air conditioning systems. Used in many industrial applications where the airfoil blade might be subjected to erosion from light dust. |
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Airfoil Blade
Although not a "Basic Type", this is an important refinement of the Backward Inclined wheel design. It has the highest efficiency and runs at a slightly higher speed than the standard flat blade to move a given amount of air. |
Most efficient of all centrifugals. Usually used in both larger HVAC systems and clean air industrial applications where the energy savings are significant. Can be made with special construction for dusty air. |
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Radial Tip
The wheel's blades are somewhat cupped in the direction of the wheel's rotation but the blade leans back so that its outside tip approaches a radial position. This fan runs at approximately the same speed as a backward inclined wheel to move a given amount of air. |
This type is also designed for material handling or dirty or erosive applications and is more efficient than the radial blade. |
