Centrifugal fans are vital in HVAC systems for efficient, high-pressure air movement and distribution of heated or cooled air, ensuring consistent indoor temperature and air quality. They use a rotating impeller to draw air in axially and expel it radially, generating high airflow against system resistance from ducts and filters. Key types, such as backward-curved and forward-curved, are chosen based on their efficiency and pressure-handling capabilities for specific applications, including industrial ventilation and air conditioning.

• Air Intake: Air is drawn into the fan parallel to the axis of the motor.
• Deflection: The rotating impeller's blades, aligned 90 degrees to the axis, deflect the air outward.
• Expulsion: The air is then expelled radially from the fan housing, creating high pressure.

• Air Distribution: They are critical for distributing conditioned air (heated or cooled) throughout a building, maintaining comfort.
• Ventilation: Centrifugal fans improve indoor air quality by moving air in ventilation and exhaust systems.
• Temperature Control: By facilitating air movement, they help regulate and stabilize indoor temperatures.