At a glance
| Forward curve | Backward inclined | Radial (paddle) | |
|---|---|---|---|
| Blades | Many small, cupped blades curved toward the direction of rotation | Fewer, larger blades leaning away from the direction of rotation | Flat blades pointing straight out from the center |
| Speed | Low | High | Medium to high |
| Best at | Lots of air at low to medium pressure, in a compact size | Higher pressure and efficiency | Dusty or dirty air and material handling |
| Noise | Quiet | Moderate | Louder |
| Typical uses | Furnaces, air handlers, fan coils, utility sets, air kits | Larger air handlers, industrial supply and exhaust | Dust collection, mill exhaust, conveying |
Forward curve wheels
Forward curve wheels, also called squirrel cage wheels, have many shallow blades that scoop the air. They move a large volume of air at low speed, which keeps them quiet and compact. That is why most HVAC blowers use them. They draw more power as airflow rises, so the motor must be sized for the system. Single inlet and double inlet forward curve wheels are our specialty, from 6" to 40".
Backward inclined wheels
Backward inclined wheels have flat or slightly curved blades that lean back from the direction of rotation. They run faster and reach higher pressures and efficiencies, and their power draw levels off instead of climbing, so they are hard to overload. We build backward inclined wheels to order in steel, stainless steel and aluminum.
Radial and paddle wheels
Radial wheels have flat blades that point straight out from the hub. They are rugged and shed dust and debris, so they suit industrial mill exhausters and material handling.
Can I swap one type for another?
Not without care. The housing, speed and motor are matched to the wheel type, so changing type changes airflow, pressure and power. When replacing a wheel, match the original. If you want better performance, call us and we'll look at the whole blower.
Questions
Is a squirrel cage wheel the same as a forward curve wheel?
Yes. Squirrel cage is the common name for a forward curve blower wheel.
Which wheel type is most efficient?
Backward inclined wheels are generally more efficient than forward curve wheels, but forward curve wheels are smaller and quieter for the same airflow at low pressure.