Belt Driven Vs Direct Drive Whole House Fan

On a direct drive fan as implied by the name the fan propeller is connected directly to the shaft of the motor.

Belt driven vs direct drive whole house fan.

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 fans have two additional bearings. You have a fan a motor and maybe a coupling.

Directive drive are louder but i think that will be the way to go for my mom s house basing on the information that you shared. More often than not the maintenance cost of this kind of fan is also comparatively lower. On both direct drive and belt drive fans the motor has two bearings. Most whole house fans are relatively easy to install.

Direct drive fans should be designed for acceptable bearing life. Unlike the belt driven fans in case of a direct drive fan there is lesser energy loss. This is because of the fact that the amount of friction is greatly reduced in case of this fan when the fan is operating. Direct drive models are the most do it yourself friendly because for most no attic joists need to be cut.

Direct drive fans require fewer parts and thus usually less maintenance. 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 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. There s also no belt residue and these fans cost less to maintain generally speaking because belts don t wear down and break.

Sizing a whole house fan. A well balanced direct drive is far quieter than belt. 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. Direct drive fans are more efficient than belt driven fans 80 vs 60 direct drive fans cost the same as belt driven fans belt driven fans challenge the filters very much because of dust coming from the belt that guy was not a direct drive fan supplier.

It s incredibly hard to balance a belt and pulley system. Greater efficiency is the biggest pro of direct drive fan configurations. It s balance or lack of balance actually which causes most of the noise. The two bearings on direct drive fan motors which are 7 horsepower and larger are typically regreaseable.

Where on a belt drive fan the fan motor shaft has a pulley connected by a belt to a second pulley. Belt drive fans are quieter than direct but still noisy.