Fan AMCA Classification
AMCA - Air Movement and Control Association International fan-class standards are established to simplify the specification of fans. AMCA fan-class standards are based on fan horsepower required per square foot of outlet area representing the structural requirements imposed on a fan for a given set of operating conditions.
AMCA class limits for a double-width airfoil centrifugal fan:
| AMCA Fan Class | Lower Range | Upper Range | ||
|---|---|---|---|---|
| Static Pressure (in W.G.) | Outlet Velocity (ft/min) | Static Pressure (in W.G.) | Outlet Velocity (ft/min) | |
| I | 2.5 | 3200 | 5.0 | 2300 |
| II | 4.25 | 4175 | 8.5 | 3000 |
| III | 6.75 | 5256 | 13.5 | 3780 |
Example - Classification of Fan
A fan working with static pressure 4.5 in W.G. and outlet velocity 3500 ft/min is within AMCA Fan Class II.
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