Direct Drive Vs Belt Drive Attic Fan

For pricing and availability.

Direct drive vs belt drive attic fan. Coming to the advantage of this kind of an industrial fan the biggest advantage is greater efficiency. Direct drive fans have no power transmission loss since the propeller is directly connected to the motor shaft. When compared to belt drive fans which require belts sheaves and bushings direct drive is just plain simpler and maintenance folks tend to lean toward direct drive for daily maintenance. This is because of the fact that the amount of friction is greatly reduced in case of this fan when the fan is operating.

Belt drive attic fans are usually much quieter than direct drive models though the latter are often cheaper. I think that the belt drive blades can turn slower with a deeper pitch than a direct drive. Attic mounts installed in the roof or exterior wall of the attic blow air directly out. Where on a belt drive fan the fan motor shaft has a pulley connected by a belt to a second pulley.

In a direct drive configuration the fan motor that controls the movement of the fan blades is connected either to a shaft or fan axle. Most whole house fans are relatively easy to install. That pulls more air with less fan noise. Unlike belt driven fans there s less energy loss because there s a reduced amount of friction as the fan operates.

Spruce spruce rb series ventilation fans 8 in steel single direct drive whole house fan. You have a fan a motor and maybe a coupling. Cool attic 24 in steel single belt drive whole house fan. Direct drive fans require fewer parts and thus usually less maintenance.

Both types are available as direct drive with the fan blade attached to the motor and belt drive with. That would be quiet but would look like a mess from outdoors. However a belt drive fan has power transmission loss due to the friction between the belt and sheaves and due to the drive shaft bearings. Unlike the belt driven fans in case of a direct drive fan there is lesser energy loss.

Greater efficiency is the biggest pro of direct drive fan configurations. Belt drive whole house fans that use an integrated pulley system take longer to install but a belt drive unit provides for a smoother and quieter operation. I fantasized building a small shack outside my house and setting the attic fan in the shack and running a duct up to the attic and through the same vent as an attic fan. Belt drive fans are quieter than direct but still noisy.

Sizing a whole house fan. Direct drive models are the most do it yourself friendly because for most no attic joists need to be cut. I had a belt drive with a two speed motor years ago.