Evaporative Cooler Fan Belt Guide: Sizes A45 to A60 and When to Replace

Belt-drive coolers use a V-belt to turn the fan from the motor pulley. Many older and larger Breezair, Braemar, Coolair and Convair models are belt-drive. Belts stretch and wear, and a slipping belt means less airflow even though the motor is working fine.

Reading the belt size

The size is printed on the back of the belt, for example A57:

• A = the belt section (width and V profile)
• 57 = the length in inches

Order exactly the same section and length. If the print has worn off, use your cooler model and fan pulley size. Each belt on our site lists the models it suits.

Signs of a worn belt

• Squealing at start-up
• Cracks across the back or sides
• A shiny, glazed surface on the V sides
• Frayed edges
• The fan runs slower than it should, or stops under load

Fitting tips

1. Turn off the power at the isolator.
2. Loosen the motor mounting to release the tension, then remove the old belt.
3. Check both pulleys. A worn or grooved pulley will chew through a new belt quickly. Replace it if needed – see motor pulleys.
4. Fit the new belt and re-tension it. There should be a small amount of deflection when you press the middle of the belt span, not slack and not guitar-string tight.
5. Check the pulleys are aligned, then run the cooler and listen for slipping.

Shop Breezair & Braemar fan belts (A45 to A60).

This guide is general information only. Always follow your cooler manufacturer’s instructions, and use a licensed electrician for any electrical work.