The High Setting on the Swamp Cooler Does Not Work

Unplug the swamp cooler from the electrical outlet and examine the cord and unit to make sure there is no external damage. Use a damp cloth and remove any dust and dirt that's built up on the vents and casing around the electrical cord. Don't use detergents, chemicals or abrasive scrub brushes to remove dust and grime. Allow the swamp cooler to rest for three to six hours before restarting. If it runs properly on low, adjust the setting to a higher speed. Cleaning, resting and restarting a swamp cooler often solves functional problems.

Maintain the manufacturer's required water level inside the swamp cooler. Visibly check the water level in your unit while it's in operation. Don't touch inside or around the electrical components while examining the water level. The Air-n-Water.com website recommends maintaining a water level that meets the water line, located slightly below the top of the tank. Unplug the swamp cooler and adjust the float arm if the water isn't at the proper level. A swamp cooler only works effectively when the water level is high enough to keep the internal pads damp. If the pads start to dry out, the swamp cooler may not work on the high setting.

Determine if the motor is malfunctioning. Turn the swamp cooler off and remove the fan belt according to the manufacturer's instructions in the user manual. Restart the swamp cooler and run the motor on high. If the motor only functions on low speed, makes chugging noises as if it can't bear the load or stops working completely, you need to replace the motor. Hire a professional or follow the motor replacement guidelines in your manual.

Examine the fan belt for cracks and worn areas. Replace the belt if it's damaged or shows signs of extreme wear-and-tear. Reinstall the original fan belt if it's in good working order, and spray the belt and metal bearings with an oil-based lubricant. Adjust the belt to ensure that there is a sufficient amount of tension, or it might slip, pull or drag at high speed. Restart the swamp cooler on low and switch to the high setting.