Simple Guide For Measuring Fan V-Belts

Replacing the belts on fans every year is a smart investment to ensure they are delivering their maximum performance. Worn fan belts can cause as much as 20% loss of cfm output.

Ordering the correct replacement fan belt is as easy taking a few simple measurements.

First, to determine what type of belt is on your fan, measure the width of the belt. Most fan belts are A type belts with a measurement of 1/2″. If the fan belt measures 5/8″ it is classified as a type B belt. You may see a belt described as type AX. The X means it has a cogged design or notches in the belt. The cogged profile increases the power transfer and typically used for only industrial applications because of their higher cost.

Next, you need to measure the length of the belt. Use a cloth measuring tape (not a steel one) and wrap it around the outside of the belt. You also use a thin string to take this measurement and place it on a steel tape to get the correct length.

Next, for “A” Belts (1/2” width) subtract two-inches from the outside measurement to select the correct V-belt. For example, if the outer measurement is 48-inches and you subtract two inches, then HSA46 would be the right belt for your fan.

For “B” Belts (5/8” width) subtract 3” from the outside measurement to select the correct V-Belt. For example, if the outer measurement is 48-inches and you subtract three inches, then HSB45 would be the right belt for your fan.

Hog Slat’s line of GroBelts offers producers top-quality V-belts at a great price. GroBelts feature wear-resistant, high modulus compression rubber embedded with polyester cords to reduce stretch. To order go to GroBelts.

Also, see our Laser Pulley Alignment Kit.  It’s a great tool to accurately check the alignment of the drive pulleys while you are changing the fan belts.