How to Decrease Evaporative Cooler Deposits

Install a bleed-off kit inside the evaporative cooler. These kits have rubber tubing that fits on your water pump and remove small amounts of water continuously, which reduces the dissolved solids in the water. As the water drains out of the bleed-off hose, fresh water enters the cooler. In areas where the water is exceptionally hard, the bleed-off water should be directed away from concrete or soil, since the dissolved solids can etch the concrete or increase the salinity in the soil, rendering it infertile.

Obtain a sump dump pump for the cooler. These are separate pumps on a timer that drain the bottom portion of the water in the cooler's pan at six-hour intervals. The pumps sit in the pan of the cooler and have a hose that connects to the overflow pipe inside the cooler. A second hose connects to the threading at the base of the pipe beneath the cooler and drains the water away from the cooler. As with bleed-off systems, the hose from a sump dump needs to be directed away from soils or concrete.

Put an inline filter between the water line and the evaporative cooler. These filters cut down on the minerals entering the cooler, effectively cutting down on the deposits that form on the pads. The filters can last an entire season. However, in areas of extremely hard water, they can plug up before the season is over, requiring replacement.

Add evaporative cooler water treatments to the pan once a week or more often if the temperatures are high and the humidity low. These products are available in hardware stores or home improvement stores. Follow the directions on the bottle for adding the liquids. These products contain mild acids that soften and dissolve hard water deposits. You can also use unscented fabric softener to reduce the scale buildup in the cooler by adding a capful once a week.

Pour a gallon of vinegar into the cooler once a month and turn off the fan but let the pump run for an hour. The vinegar loosens the salt deposits inside the pads. Shut the power off to the cooler and pull the plug. Remove the access panel to take out the overflow pipe, which drains the cooler. Once the pan is empty, remove any dirt and debris using a flat scraper. Replace the overflow pipe and fill the cooler with fresh water.