How to Run an Evaporative Cooler & Humidifier

Evaporative coolers and humidifiers do double duty by providing cool-air relief on hot summer days, or adding moisture to dry indoor winter air. Evaporative coolers/humidifiers are run in similar fashion to many portable humidifiers: you add water to a tank area, then select a fan speed based on the amount of relief you'd like in the room. The cooling process works by drawing hot air in from a nearby window while blowing water-cooled air into the room. Even if you do not have instructions for your cooler/humidifier, basic operating methods are similar from brand to brand.

Positioning is Key

  1. Positioning is perhaps the most important aspect of running an evaporative cooler/humidifier. When in cooling mode, these units require a partially-opened window to draw in hot air through the back of the unit. A fan within will blow water-cooled air wherever you'd like. Movable vent flaps on some models will provide additional control over air flow. Using the unit as a humidifier won't require an open window, but the device should be kept in an area where it won't be bumped, to avoid spillage.

Water and The Water Tank

  1. Evaporative coolers and humidifiers require water to function properly. All units have a water tank, though the positioning varies from model to model. Consult the instruction manual or manufacturer's website whenever possible. Otherwise, the tank is likely behind a door or panel that you can easily open. Tanks should be at least half full whenever in use. They require monitoring so they don't dry out. Note the inside of the tank or receptacle for filling lines.

Filter Importance and Maintenance

  1. Fans are an essential part of evaporative coolers; air is continually drawn into and blown out of the unit. Where there's a fan, there's a filter. The filter helps keep dust, dirt and other airborne particles that enter the unit from being blown out into the room. Like filters in central air conditioning and heating units, evaporative cooler/humidifier filters must be cleaned from time to time, or even replaced. Searching the flaps or panels on the unit will uncover the filter area. Once you remove the filter from the device, tap it out over a trashcan, then gently vacuum it to remove loose particles and debris. If you ever need to replace the filter if it becomes damaged or permanently clogged, consult the manufacturer's website or instruction booklet to learn where to buy a new filter.

Cleaning as Routine Maintenance

  1. Like other appliances, the evaporative cooler/heater functions best and most safely when clean. Wiping the outer surfaces (as well as areas near the cooler) with a damp sponge will help prevent particles from entering the cooler. The water tank will also need cleaning from time to time; gentle soap and water and a clean-water rinse will do the trick. If you aren't going to use the cooler for some time, empty and dry out the water tank to prevent bacterial buildup.