How to Remove Calcium Buildup From a Swamp Cooler

Swamp coolers, also known as evaporative coolers, use considerably less energy than air conditioners to cool indoor spaces. They work well in a hot, dry Mediterranean-type climate like that found in the Southwestern U.S. where they not only keep your home cool but add some humidity. However, if they're not properly maintained, calcium deposits may form.

Swamp coolers use water that's injected into indoor air, causing that air to condensate, which then cools the air. But the water in some dry climates like that in Arizona tends to be hard. That means minerals like calcium can build up on swamp cooler pads and, eventually, corrode the cooler's metal covering.

At the start of each cooling season, inspect your swamp cooler for calcium buildup. You should also make sure you use good-quality swamp cooler pads. You'll typically need to change them two or three times each season, but you may need to change them more often. It's a good idea to check them monthly.

Also, make sure you clean the inside of your swamp cooler unit at least once a month. A mixture of white vinegar and water should do the trick. While you're at it, use the vinegar and water mixture to clean the water pan reservoir at the bottom of the cooler to keep calcium buildup to a minimum. That also prevents debris from gumming up the works and allows clean water to get to the pads.

Swamp coolers, like most cooling and heating units, need regular maintenance to keep them in good working order. A thorough cleaning before the cooling season begins is the best way to get your unit ready for hot weather.

Check the fan belt to make sure there's very little movement. If it's loose, you can try to tighten it, but if it sags, you'll likely need to replace it. Also, lubricate the blower assembly and the motor with the proper oil for your unit.

Scrub the panels using soap and water. You may need to scrape away any buildup with a wire brush. Also, inspect the wiring and switches to make sure there are no worn or damaged parts. Check that your water supply is adequate.

There are some items that can help you keep your swamp cooler from becoming clogged with calcium and other mineral deposits. A purge pump works to pump out water from the pan and bring in fresh water. You can also install water filters that trap calcium and other minerals before clogging your pan. There are tablets you can release in the cooler pan that will improve water quality and prevent calcium buildup.

After the warm season is over, drain the cooler and clean it to remove any buildup of calcium and debris. Cover the unit with a canvas cover until the start of the next cooling season.

Check for calcium buildup in your water distribution line. If these get clogged, they'll reduce water flow to your pads, and this could eventually cause your cooler to blow hot air into your home. Also, check for calcium deposits on your water pump. Calcium buildup can reduce the pump's ability to pump water into the distribution tubes, and it can corrode your pump.