Evaporative Cooler Troubleshooting

When summer approaches, so does hot weather. If you reside in a dry, arid climate and wish to stay cool and comfortable during the warmer months, it may not be a bad idea to consider purchasing an evaporative cooler to efficiently and cost-effectively cool your home or workplace.

History of the Evaporative Cooler

Evaporative cooling has been in existence since antiquity. An early form of the evaporative cooler, the windcatcher, was invented in Persia and consisted of wind shafts placed on the roof of buildings. These shafts would catch the wind, pass it through water, and blow the cooled air into the building.

Although modern evaporative coolers are a bit more advanced than these primitive air coolers, the cooling method still remains the same.

How They Work

Evaporative, or swamp, coolers are essentially large box-like frames containing large fans. Water-moistened pads made of wood shavings or cellulose are walled within the frame and continually soaked by a water pump, and the fan blows hot outside air through these pads.

As a result, this water-cooled air is blown out through a vent, and this can lead to temperature reductions of up to 20 degrees Fahrenheit.

Suitable Climates

Because evaporative coolers add moisture to the air, they are only suitable for climates where the air is hot and the humidity is low. High temperature and humidity levels can decrease the cooling capability of the evaporative cooler, and high humidity in the air can also accelerate corrosion and cause condensation.

However, for those who live in areas suitable for evaporative coolers, this type of cooling can be one of the most energy-efficient methods of cooling a home. In fact, evaporative coolers can cost about half as much to install as central air conditioners and use about one-quarter as much energy.

Evaporative Cooler Maintenance Requirements

Nonetheless, evaporative coolers may require a bit more maintenance than refrigerated air conditioners. Evaporative coolers require water to keep the pads wet, and since the tanks need to be filled with water to ensure proper cooling, this can take anywhere from 3 to 15 gallons of water per day, depending on the unit.

Also, the pads will need to be periodically replaced to prevent debris or bacteria build-up. So without proper maintenance and regularly inspection, it may be difficult to determine why an evaporative cooler is not running efficiently, or even if the unit is being over exerted.

Here are some general tips on evaporative cooler maintenance:

• Check the water level in your evaporative cooler's tank to ensure that it is at the proper level in the tray. Make adjustments to the float arm if the water is not at the proper level.
• Change the cooling pads frequently. Twice seasonal pad changes are ideal.
• If your evaporative cooler manufacturer recommends water treatment tablets, use these in your evaporative cooler to control corrosion, prevent mineral build-up, and to freshen the air.
• Regularly inspect the motor, bearings, belt, and amp draw.

If you notice that your evaporative cooler is still not operating correctly even after routine maintenance, see if the following situations apply to you:

My evaporative cooler doesn't start and/or deliver air.
Check the fuse or breaker for the cooler, and if you notice that the fuse is blown or the breaker is tripped, either replace the fuse or reset the breaker. If the problem still continues, check the wiring within the unit for signs of damage.

My evaporative cooler is running, but there's insufficient air.
Ensure that there is enough exhaust supplied to the unit. For portable evaporative coolers without exhaust ducts, be sure that the windows or doors are open enough to allow for proper airflow.

We generally recommend that a 2 square opening is to be allowed for each 1000 CFM, and if there's sufficient exhaust, check the motor and belt tension.

There's sufficient airflow but inadequate cooling.
Make sure the water pump is operating and not clogged. Also check the cooling pads, as dry or open spots on the pads can hinder your evaporative cooler's cooling abilities.

My evaporative cooler uses too much water.
Excessive water use can result from a problem with the valve. If you notice a water leak or problem on the seat of the valve, this should be replaced.

There is a musty odor coming from my evaporative cooler.
Odors can be caused from either stagnant water or mildew on the pads. Prevent stagnant water by draining and cleaning the evaporative cooler's reservoir and replacing it with fresh water. If the problem lies within the pads, check these and have them replaced if necessary.

The parts within my evaporative cooler are showing signs of corrosion.
Corrosion and rust in an evaporative cooler can be due to minerals in the water tank or even high humidity levels in the outdoor environment.

If you have a mineral problem, try adding mineral tablets to the water tank. On the other hand, if there is excessive humidity - above 50 percent - the evaporative cooler may not work efficiently, and you should consider purchasing a portable air conditioner instead.

Lastly, if the above troubleshooting steps don't solve your problem, contact a professional or your evaporative cooler's manufacturer.

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