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The Ultimate Guide to Understanding Evaporative Cooler

evaporative cooling

The Ultimate Guide to Understanding Evaporative Cooler

In this new guide, you’ll learn about what is evaporative cooler and how it exactly works, tips to keep your cooler run efficiently and when it is time to repair it.

There is no doubt that evaporative cooler is a very important element for your home, so we’re happy to help you understand all about it.

Evaporative cooling Fundamentals

To understand your Swamp cooler, you need to know all the working parts.

Without one, the others don’t work.

So, what is the Evaporative cooling System?

Evaporative air conditioners use evaporation to cool the air. Inside an evaporative cooler, a pump keeps the water circulates from the tank onto a cellular pad, which becomes very wet and always loaded with water. At the same time, a fan draws air from outside the unit –hot air- through the wet pad. While the hot air passes through the pad it is cooled by evaporation.

Principle of Evaporative cooling

While water evaporates, energy is lost from the air, causing to reduce the temperature. When we talk about evaporation, two types of temperature are important:

• Dry Bulb Temperature

This is the type of temperature that usually expressing the air temperature, it can be measured by a regular thermometer exposed to an air stream.

• Wet Bulb Temperature

This is the lowest temperature that could be reached just by the evaporation of water.

If we have a deep observation on water evaporating into the air, the wet-bulb temperature, as compared to the air’s dry-bulb temperature is a measure of the potential for evaporative cooling.

Evaporation happens when the humidity is less than 100%, then the air begins to absorb water. Any specific volume of air can hold a certain amount of water vapor and the amount it will absorb depend on the amount it is already holding (humidity percentage).

While air conditioners rely on the vaporization and condensation processes of a liquid refrigerant, portable air coolers depend on the principle of evaporative cooling. This process could be summarized as the following: As you pour water into the device reservoir then water turns into vapor, during the evaporation process heat pulled from the surrounding air, and water droplets spread around causing a cooling effect.

Evaporative cooling is a natural phenomenon that happens all around us. Remember when you step out of a pool on a very hot day and suddenly feel a chill. Or when you sweat and after few minutes you feel the cold air on your skin. These cooling effects happen while dry air passes over water drops, the dry air will logically carry some of the water. Because heat switches from the higher air temperature to the lower water temperature the area around the evaporative cooler are cooled.

To make it simpler to understand, the two main components of an evaporative cooler comprised of:

1. Cooling pads (a filter that is saturated with drops of water)

2. Fan (to pull out the cooled air from pads and spread it around your area)

In addition to some other components like the water tank (you’ll need to add water constantly when the water level controller alerts you) and a pump to keep the circulation of water through the pads and make them always loaded with water.

Types of Evaporative Air Coolers

Portable swamp coolers(Air Cooler Fan) – That style can be easily moved from one place to another.

Window-mounting– convenient coolers that save more space and cover larger areas. A suitable solution for small rooms and workspaces, it has the advantage of constant access to fresh air.

Roof-mounting – This type of evaporative air coolers is a common solution for commercial/industrial environments but is not recommended for personal application. These units need air ducts, and they’re more likely to require expensive maintenance over time. But, installation is very simple, especially if the appropriate air ducts are already installed in the building.


Maintenance of Your Evaporative cooler

You should have your cooler serviced twice a year, before to the operating season and midway through summer. This regular maintenance will help to extend the life and efficiency of the equipment.

You can save yourself a lot of work and money by draining and cleaning your evaporative cooler from time to time. Sediment and minerals that built-up should be removed regularly. Coolers need a good cleaning every season, and also need a routine maintenance many times during the cooling season.

The more you run the cooler the more maintenance it will logically need. If you’re living in hot climates where the cooler operates most of the day, always check the pads, filters, tank, and pump let’s say once a month. You may need to replace the pads twice during the summer season, or once a month in the case of continuous operation.

Some types of cooler pads can be cleaned with soap and water or a weak acid; you can refer to the manufacturer’s instructions for more assurance. Make sure to clean the filters cleaned when you change or clean the pads. And for your safety, disconnect the electricity to the unit before any of previous steps.

Caring for your swamp cooler, Tips for Simple maintenance:

Before starting up the unit, perform these simple maintenance steps:

• Take off old pads and then clean pad frames. You can use a wire brush to scrape away built-up scales. Then paint all surfaces with a cooler protectant.

• Drain and flush the tank. Then scrape away scales and paint with protectant.

• Clean the water distribution system (pump screen, pump impeller, and the tubes), replace any broken tubes and lubricate the pump impeller with SAW 20 motor oil.

• Check the electrical wires and switches for bad connections or worn insulation. Inspect the belt for any cracks or wear then replace or repair worn parts.

• Inspect the motor set and adjust the motor bolts.

• Turn on the water system and make sure that water is covering the entire cooler pad. Notice that too little water will cause dry spots and may reduce the cooler’s efficiency.

• Observe the water level in the reservoir. Adapt the float valve to settle about three inches of water.

• Replace the cooler pads-if needed- and fix the frames.

As mentioned above, the first five steps must be performed at operating season’s end and twice through the summer. If you won’t need to use the unit during the winter, shut off the water supply system and disconnect the electricity from the unit. Then fully drain the water from the reservoir to prevent possible freezing through the winter. Close the duct dampers and cover the unit. Now you’re all set to store your swamp cooler.