Home› Products› How to Choose a Centrifugal Fan
Sizing and selecting a centrifugal fan correctly starts with five things: airflow, static pressure, impeller size, motor type and mounting. Here is how to get it right.
Start with the air volume you need to move, in m³/h or CFM. For room or equipment cooling, calculate from heat load. For ventilation, use air changes per hour. This number sets the minimum capacity of your fan.
Static pressure (Pa) is the resistance the fan must overcome — from ductwork, filters, coils and grilles. A system with long ducts or dense filters needs higher static pressure. Always check the fan's airflow vs. static pressure curve to confirm it delivers your required airflow at your system's resistance.
Impeller diameter is the main driver of capacity. Centrifugal fans by ANENG range from 133mm to 710mm. A general rule: larger impellers move more air and generate more pressure but take more space. Your airflow/pressure point determines the right size.
| Motor | Best For | Trade-off |
|---|---|---|
| AC | Simple, fixed-speed, low budget | Lower efficiency, no speed control |
| DC | Low-voltage, controllable applications | Needs DC supply (e.g. 24/48V) |
| EC | Energy savings, ErP 2026, variable speed | Higher initial cost |
Decide whether the fan mounts in a duct, on a panel, or inside equipment. Check inlet/outlet orientation, wiring options and protection rating (IP44/IP55) for your environment. For OEM, ANENG can customize all of these.
Airflow is how much air moves; static pressure is how much resistance the fan can push against. Both matter, and you need a fan whose performance curve meets your system at the required operating point.
Backward-curved impellers are more efficient and better for higher-pressure systems; forward-curved impellers are more compact and better for low-pressure, high-flow applications at lower cost.
Yes. Share your airflow, static pressure, voltage, size and mounting needs and our engineers will recommend the right AC, DC or EC centrifugal fan, standard or custom.
Send us your airflow and static pressure specs and we'll match the right centrifugal fan for your system.
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