Attic Fan Belt Deflection

You can then use an app or a chart like this one to find the proper force to generate this deflection.

Attic fan belt deflection. Conversely an improperly tensioned belt can cause a host of easily preventable problems including noise vibration poor fan performance bearing wear and shortened fan motor life. Set the large o ring on the tensiometer to the desired deflection determined in step 2. Desired belt deflection is 1 64 of an inch for every inch of belt span. So for a 5 rib belt you will need to multiply the force shown in the.

A space between the belts should be about 1 3 4 at proper belt tension. Set the small o ring on the tensiometer to the zero mark. For example if the span length is 32 inches the desired belt deflection is inch. Dispose of the broken fan belt or pieces of the belt in the trash.

Slowly rotate blade one full revolution by hand to. To deflect the belt 1 64 for each 1 of belt span q. Pull one end of the old fan belt off from around the hub connected to the motor shaft. Test belt tension with power off squeeze belt together with light force.

Lift the belt out of the fan if the fan belt is broken in half pull the two sections off the hubs and lift them out of the fan. A properly tensioned belt ensures smooth operation and extends the service life of fans and motors. So for a 32 span the deflection amount would be 32 64 or 1 2. Pull the other end of the belt off the other hub inside the fan.

Adjust the motor back until there is approximately 1 2 1 3 cm to 3 4 1 9 cm deflection at the center of the belt with light pressure.