What is an Evaporative Air Cooler?
An evaporative air cooler cools rooms in the same way that your body naturally cools itself through sweating. They require a water connection and must be filled with safe, sanitary water.
Most models have a remote control, LCD panel and features like varying fan speeds, oscillating mode and ice tanks. Some even have a bactericidal treatment in the water tank to help prevent mildew and bacteria.
1. Evaporative Cooling
Evaporative cooling takes advantage of the natural process of evaporation to cool air. It is a simple system that is effective in arid climates. Unlike traditional air conditioning, it does not dehumidify.
A fan draws outdoor air into the evaporative cooler and across thick pads that have been saturated with water. As the air passes over the pads, it absorbs heat through evaporation and reduces the temperature of the air by as much as 20 degrees.
The resulting cooler, dry air is stand fan with water spray then directed into the house through vents. Optional filters help clean the air and can reduce mildew growth and allergens in your home. In humid climates, evaporative cooling may not be as effective as it is in arid regions.
This is because very humid air makes it more difficult for water molecules to evaporate and cool the air. It is the same reason why your body sweats more on a hot, muggy day than on a dry one.
It is also why evaporative cooling works well in the Southwest, including California, Arizona, Utah, Colorado and New Mexico. Evaporative cooling is most effective in areas where the average annual humidity is less than 65% and the relative air temperature is over 74°F. (See the map below for a general idea of these climate zones.) Humid air has a high wet bulb temperature, meaning that it is more difficult for water to evaporate and cool the air.
2. Humidity Control
Evaporative cooling systems use the natural process of evaporation to lower air temperatures. It’s much like the way that a lakeside breeze feels cooler than air flowing inland because it is carrying water vapor with it. The cooling effect works by converting the heat energy into evaporative energy, which is a much more efficient process than just blowing air around.
This is very different to how standard fans work. A normal fan blows air around, which could feel cool on a hot day, but doesn’t decrease the temperature of the air itself. An evaporative cooler does this, however, by using the natural process of evaporation to change the temperature of the air and provide a more sustained coolness.
When the evaporative cooling pad is wet, the fan draws the air over it, and this causes the water molecules to evaporate. This decreases the overall air temperature, so the resulting cool air is significantly lower than the ambient room temperature.
The evaporative cooling system is also more effective when there is less humidity in the air. The ideal indoor humidity level is between 40 and 60%, which reduces the spread of bacteria and other organisms, improves respiratory health and helps prevent condensation on surfaces.
If you live in a hot and dry region, an evaporative cooling system can be very economical, providing cooler, more comfortable indoor air. For the best results, ensure your evaporative cooling system has exhaust ducts and/or open windows to enable the free flow of air to and from the interior.
3. Energy Efficiency
Evaporative coolers use basic evaporation to automate the cooling process and achieve significantly lower temperatures than refrigerated air conditioning. The machine draws hot air in and across a pad that’s been wetted with water from a reservoir, causing the water molecules on its surface to evaporate and cool the air passing over it. The resulting cooled air is then blown around the room.
This cooling method is more efficient than refrigerative air conditioners, consuming 75% less energy on average and producing fewer harmful greenhouse gases. It is also cost-effective and environmentally friendly, relying on water rather than harmful chemicals to function.
As a rule of thumb, an evaporative cooler uses only two components that require power; a fan and a water pump. Domestic evaporative air coolers typically draw between 200 to 400 watts of electricity, and this can vary depending on size and features.
Because the cooling process is based on a natural process, evaporative coolers are also more eco-friendly than refrigerative air conditioning systems. The only byproduct of the evaporative cooling system is water vapour, and this doesn’t deplete the earth’s ozone layer or contribute to climate change like many refrigerant chemicals do. This is why the evaporative cooling system is considered to be an ecologically sustainable cooling solution for buildings and homes.
4. Environmentally Friendly
Evaporative cooling systems are a great alternative to air conditioning units, which use harmful stand fan with water spray wholesale refrigerant chemicals that deplete the earth’s ozone layer and contribute to global warming. Swamp coolers use no gases or compressors, meaning they are more environmentally friendly and require less maintenance.
In addition to being environmentally friendly, swamp coolers also improve indoor air quality by reducing dirt and pollutants in the air. They add moisture to the air, which can help reduce dryness associated with drier winter climates and may also help to alleviate a range of conditions, including asthma and allergies.
To maximise the benefits of evaporative cooling, it is best to keep windows and doors open as much as possible while the machine is operating. This allows the warm air to pass through the damp pads, which causes evaporation and cools the air. It also ensures that fresh air is continuously being brought into the home, rather than recycled air like standard air conditioners which can leave a space feeling stale. This can also reduce irritation for people with allergies and asthma as the cooler does not dry out the air, which can irritate their eyes. For best results, ice compartments can be used in the warmer weather to enhance the cooling effect, but it is important not to overdo this, as too much ice will slow down the evaporation process.
