Belt Drive Vs Direct Drive Attic Fan

It s balance or lack of balance actually which causes most of the noise.

Belt drive vs direct drive attic fan.

Unlike belt driven fans there s less energy loss because there s a reduced amount of friction as the fan operates. Most whole house fans are relatively easy to install. With a belt drive the fan speed can be easily raised or lowered but there is belt and bearing maintenance to consider with a belt drive there are 2 additional bearings. 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.

Direct drive fans require fewer parts and thus usually less maintenance. Sizing a whole house fan. 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. Direct drive models are the most do it yourself friendly because for most no attic joists need to be cut.

A well balanced direct drive is far quieter than belt. 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. Unlike the belt driven fans in case of a direct drive fan there is lesser energy loss. It s incredibly hard to balance a belt and pulley system.

Where on a belt drive fan the fan motor shaft has a pulley connected by a belt to a second pulley. Greater efficiency is the biggest pro of direct drive fan configurations. That would be quiet but would look like a mess from outdoors. Direct drive fans have no power transmission loss since the propeller is directly connected to the motor shaft.

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. Thus the fan blades will rotate at the same speed as the motor rotates. This is because of the fact that the amount of friction is greatly reduced in case of this fan when the fan is operating. You have a fan a motor and maybe a coupling.

The second pulley is connected to a shaft that drives the fan propeller.