Consider The Evaporative Cooler Option

June 3, 2016

When the weather heats up, how do you keep your home cool? While conventional air conditioning is always a solid choice, evaporative coolers, on the other hand, are often an overlooked option. How do evaporative coolers work, and how do they compare to air conditioners?

How Evaporative Coolers Work

When water evaporates, it cools down the surrounding air. Think of how human bodies use the process of evaporative cooling, i.e. perspiring, as a way to regulate our body temperature.

Evaporative coolers, also known as ‘swamp coolers,’ work in a similar fashion. An evaporative cooler contains water-soaked pads, and as outside air is pulled through the pads, the water evaporates, thus cooling the air. This cooled air is then blown into your home through an independent ducting system, pushing out the hotter indoor air through your home’s open windows. With evaporative cooling, it is necessary to provide a way for the warmer indoor air to be exhausted from your home during system operation, and windows are typically the chosen means. An evaporative cooler can reduce air temperature approximately 15 to 30 degrees Fahrenheit, depending on outdoor conditions and equipment design.

If you’ve recently moved to Colorado from a more humid area such as the East or West Coast, you may not be familiar with evaporative coolers, which are only effective in areas with relatively low humidity. This is because the dry outside air is used to evaporate water from the media pads in the cooler. If the air outdoors is very humid, it won’t pick up the water, and the cooling effect can be minimal or nonexistent. Throughout much of the summer, the air around Denver and Boulder is generally dry enough to produce effective cooling. However, during our brief summer ‘monsoon season,’ an evaporative cooler’s effectiveness may be diminished. If you’re someone who prefers the slightly humidified, cool fresh air that a swamp cooler supplies, you like having some windows open, and your cooling needs throughout the season are not highly specific, then an evaporative cooler might be a good choice for your family.

The Fresh Air Factor

A traditional central air conditioning system recycles the indoor air throughout your home while it’s being cooled. If you maintain the system well and have a good air filter, the system removes lots of dust particles and can keep your indoor air clean and healthy, even for people who suffer from allergies.

Evaporative coolers, however, continuously bring in large amounts of fresh air from the outside. If you’re thinking about purchasing an evaporative cooling system and you have significant allergy issues, you may want to rethink this decision. Evaporative coolers do not effectively filter out outdoor allergens, and this type of cooling system may not be the best choice for you.

Efficiency, Cost, and Maintenance

While a professionally installed, centrally ducted evaporative cooling system may not cost a whole lot less than installing central AC, a big advantage of this type system is that evaporative coolers use about one-fourth of the energy of air conditioning to operate the system–a real boon to your utility bill! This difference can vary, depending on the efficiency levels of systems you are comparing.

Many ‘modern’ evaporative coolers now contain automatic-flush/fresh water systems, so concerns about stagnant water and needing to manually clean out the reservoir throughout the summer, are no longer an obstacle to owning a new cooler. Old-style, square, metal evaporative coolers, still popular, may still present this potential concern for some systems.

Some of the current high-end coolers also offer improved cooling performance and additional features like programmable, digital thermostats, high performance blowers, and high efficiency motors, which were not available 10 or 20 years ago. If you’re not familiar with these latest design innovations, take the time to get up to speed before you rule out evaporative cooling.

Regarding annual maintenance, keep in mind that an evaporative cooler is a water-based system that requires a thorough startup and shutdown procedure at the beginning and end of the season: If ignored, you will likely be dealing with frozen pipe issues. Some handy homeowners choose to do their own swamp cooler servicing and save themselves money on service calls. In many cases, this can be a reasonable plan for years.

Worth noting: Unlike AC systems, an evaporative cooler will never incur the expense of adding refrigerant, or require time-consuming pressure testing or evacuating if a small leak should occur.

In comparison, a central AC system also requires annual maintenance, normally just one comprehensive visit per season. This service requires specialized tools and training that are typically beyond most homeowners. While the furnace filter often requires additional changing during the cooling season, many homeowners take care of these important replacements themselves. (Neglecting to change the filter can potentially lead to myriad and costly problems!)

So it is difficult to blanketly say that, over the life of the system, one cooling option is more or less costly to maintain than the other.

Which System Makes Sense For You?

Evaporative coolers aren’t for every home or family, but they are a solid cooling option worth considering for folks who live in relatively arid areas like the Denver and Boulder area. As with virtually all home comfort systems, evaporative cooling and air conditioning each have their advantages and disadvantages. Our advice: When you start shopping for a new cooling system, get in touch with a qualified professional who is willing to come out and carefully inspect your home and listen to your desired goals. An experienced HVAC contractor who works regularly with both air conditioners and evaporative coolers will be able to assess your situation, discuss options, and make cooling system recommendations that make sense for your unique situation.