A Guide To Evaporative Coolers

Evaporative coolers, also known as swamp coolers, have become a top choice for anyone looking for an alternative cooling solution from their home or office. In the past, evaporative cooler technology was limited for use in large operations that have easy access to exterior air, such as factories.

The technology has grown leaps and bounds over the last decade, and now portable units have all the features of the standard air conditioner. Apart from all these added features, evaporative coolers have become a superior choice over traditional air-conditioners. Swamp cooler technology has now been compacted into smaller units that suit the home and office.

How Evaporative Coolers Work?

Evaporative coolers harness the power of nature, particularly the cooling effect of evaporation. Have you ever been relaxing by a lake and felt a cool breeze come across the surface and land on shore to refresh you? This is the working principle that is behind evaporative cooling.

As warm air passes over or through a body of water, a latent heat exchange occurs as the water is evaporated by the warm air, pushing the warmth into the water and cooling the air.

How Evaporative Coolers Work?

An evaporative cooler harnesses this process through a fan housed within the unit, pulling warm air from outside into the unit and through a set of cooling pads that are constantly wetted. The air then undergoes the latent heat exchange, and the fresh, cool air is then pushed into the room, where it cools the ambient temperature.

Evaporative coolers are inexpensive to operate, and they can offer a power saving of up to 70% compared with other traditional air-conditioning systems. This is because there are very few electrical components within the evaporative cooler unit.

Inside the unit, you will find a thermostat to control the operation of the cooler, as well as a water pump that pushes water over the cooling pads and an electric fan to pull in the warm air and expel the cool air.

Evaporative Coolers VS Air Conditioners – The Difference

Since evaporative coolers require less energy to operate, they also have a unique method of operation for the unit to operate at its full, efficient capacity. In traditional air conditioning system, you are required to seal the room that needs cooling by closing all the doors and windows and then go about consistently remediating and cooling the room’s air.

Evaporative coolers work by forcing new, freshly cooled air into the room; therefore, they require an exhaust point in order for the old, spent air to be expelled from the room as the new air replaces it.

Therefore, you will need to open a window or leave a door slightly open for the exhaust air to escape. Should you fail to open a window and create the negative pressure needed for the air to escape, the room will slowly increase in relative humidity to the point where the room’s surfaces begin to become damp and wet. This may destroy wooden furniture and window frames and damage electrical equipment and other household items such as painting, books and carpets.

Maintaining Your Evaporative Coolers

We would never have to lift a finger to do anything in an ideal world. Food would magically appear before us when dinnertime was near, and our teeth would brush themselves in the morning. These things will never happen. A certain level of energy must be spent to receive a reward, and this is life.

The same principle applies to your evaporative cooler. In an ideal world, we would simply turn the unit on, and it would run for the entire summer with no hassles. However, things are not this easy in life, and your evaporative cooler will require some minor maintenance to keep it running at optimum efficiency.

While your evaporative cooler only requires a minimal amount of maintenance, it’s still important to make sure that you do the following;

The Housing

Before the relentless heat of the summer arrives, it’s time to do a quick check-up on your cooler. Begin by removing the weather cover and giving the external housing a quick check over for signs of cracking around the reservoir or fan grids. Ensure that the fan grid is clean and free from debris such as dust or leaves.

Pump, Pads and Filter

Next, remove the housing to expose the reservoir, water pump, cooling pads and fan. Clean out the reservoir and make sure all sediment that could possibly clog up the water pump is removed, wipe down the reservoir and then turn on the unit to make sure that the reservoir fills and that the water pump is functioning correctly, pushing the water over the cooling pads.

Next, turn the unit off again and remove the cooling pads and the filter. Wash them with a light soapy solution and then rinse them clean with fresh water before reinstalling them into the unit.

The Fan

Check the fan impellers for signs of wear, and then wipe them down to remove any dust or debris. Give the impeller a quick turn or two to ensure the bearing is working correctly, and then spray them down with a silicone-based lubricant.

Thermostat and Electrical Circuits

Next, make sure the reservoir is filled with fresh water and switch on the unit for a test run. Use your control panel or remote control and turn on the unit. Ensure that the temperature settings are working and other electronic features such as the fan swing are functioning correctly.

The Final Check

For the final step, reassemble the housing and make sure that it is fitted securely, then wipe the unit down to remove any dirt, dust or debris that may have been collected in storage or out in the open during the winter months. You are now ready to operate your unit!

At the end of the season

At the end of the summer season, after days of effective and efficient cooling, it’s time to pack your unit away. Empty the reservoir and clean the air-inlet grille and fan impellers. Then reassemble the unit and cover it with a weather cover if it is an exterior mounted unit or a plastic cover to prevent dust build-up. It is a smaller portable unit that you can store in your garage or cupboard.

What if something goes wrong?

If you discover a fault with anything on the list, call your manufacturer or agent and arrange a technician to come out to your property to service the unit. For external units, you may have to have a call-out; however, if you have a lighter, portable unit, then just pop it into your car and take a drive to your agent where they can give it a service for you.

The Final Thought

While machines such as evaporative coolers are built to improve our quality of life, they still need some TLC to run at their optimum efficiency and effectiveness. There is nothing like a free lunch. Completing these few simple steps before turning on your unit will greatly extend its operating life, providing you with further maintenance savings alongside the dramatic electricity savings that you can expect from an evaporative cooler.

Worked in IT for 10 years, specialising in computer measurement, resource and performance management and complex problem solving. Changed careers to HVACr in 2015.

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