HVAC Fan Types

hvac fan in MOAccording to current research, more than 25 percent of the energy consumed in commercial buildings is used for heating and air-conditioning. Within that 25 percent, anywhere from 20 to 60 percent is consumed by the HVAC fans and pumps that transfer heated and cooled air or water from central heating and cooling plants to the various locations. Supply and exhaust HVAC fans will typically operate continuously while the building is occupied.

There are two basic types of HVAC fans: axial and centrifugal. Axial-flow HVAC fans are the stereotypical propeller-type fans much like an oscillating floor fan that is placed in your home. In many instances, axial fans are directly connected to the motor controlling them which avoids energy loss through belt drives. Typically there will be a central hub where the motor fits behind the fan increasing efficiency. Weight distribution within the fan blades further increases efficiency and allows for a low starting torque.

Centrifugal fans are quite a bit different than axial fans. Instead of air passing straight through, the air makes a 90-degree-angle turn as it travels from the inlet to the outlet. This causes the air to be “thrown” from the blade tips. Centrifugal fans have more mass farther from the axle, which requires it to have a higher starting torque. The benefit is that centrifugal fans are quieter than axial fans.

Within both HVAC fan types there are several sub-categories of options whether you are looking for higher volume of air, increased suction, twisting air, higher efficiency designs, ability to pass foreign objects, and cost advantages.

To schedule HVAC installation or repair service near Overland, contact us today at American Services in Saint Louis, you won’t be disappointed!