Evaporative Cooler Reviews
The difference between an evaporative cooler and an air conditioner isn't just the naming convention. An air conditioner "conditions" the air by not only cooling it, but removing moisture from the air as well. The dehumidifying aspect increases comfort. An evaporative, or air cooler, on the other hand, works by adding moisture to the air while lowering the temperature.1
In both systems, heat is eventually moved outside the building. The real advantage of a portable air conditioner is that, unlike fixed venting to the outside, any open window will allow enough air exchange for the portable to work. This makes it truly portable – no venting hoses are required.
The proper name for an air cooler is an evaporative cooler. This refers to how they work – water evaporation. They are also sometimes called swamp coolers or desert coolers.2 These units work by blowing hotter, less humid room air over moist pads. The moving air evaporates water from the pads, taking heat energy from the air. The result is a cooler, moister air blowing out the other side.3
Because portable air coolers consist of a fan to blow air and a small water pump to keep the pads moist, there isn’t much technology involved. This keeps the prices low, a major advantage of these systems. Another is the light weight. Portable AC units start at about 70lbs for the smallest, while an evaporative cooler can weigh as little as 17lbs before adding water.4
Advantages and disadvantages of evaporative coolers
The major advantage is cost to purchase and run. Portable air coolers are several hundred dollars cheaper to buy and only use about as much energy as a couple of light bulbs to operate. In drier environments, they also add moisture to the air. And, they are truly portable. Unfortunately, they also have some real disadvantages.
They will not work well, if at all, in parts of the country where summer humidity is moderate to high. Since they depend on water evaporation to work, desert or dry climates are best.5
They are limited in the amount they can cool. While in the best circumstances, a portable air cooler will deliver cool air as much as 30 degrees lower than ambient temperature, they limit out at about 65 to 70 degrees coming out of the unit. This means that they cannot push out enough cold air (or air that is cold enough) to cool more than a small area.
They may provide an environment for mold or mildew growth. Since they use always moist pads, and are used in a warm setting, fungi and other things find them an attractive place. Users are cautioned about proper cleaning and disinfection, but improper maintenance will lead to smells from growing organisms.
They require a water supply. For portable air coolers, this comes from a tank that has to be refilled periodically. The more cooling required, the more water, and the more often a unit will have to be filled up. At max cooling, a unit may need two refills a day.
Manufacturers and models
Kuulaire offers seven different models of portable air conditioners, ranging in capacity from 100 to 600 square feet.6 They all have remote controls and timers. Larger units have detachable water tanks to transport water. Some have low water alarms as well.
Prices range from just over $100 up to $600. The largest units are sold under the Port-a-cool brand.6 Shopping online is available and they partner with Home Depot, WalMart, Best Buy, and Air-n-Water.
Sunpentown makes several smaller portable coolers and are well respected in this market. They refer to them as “personal coolers.” Prices hover around $100 for all their models and they limit out at about 150 square foot capacity.
Fuzhou Green7 is a Chinese manufacturer with a line of portable evaporative coolers popular in Asia, Australia and Europe. They list North America as an export destination, but no current U.S. retailers were found online. Prices on their site are listed as “negotiable” – expect to see this product line for sale in the near future in the U.S.8
Symphony makes 14 different models9 of portable coolers in several styles and prices. They range from a personal size at about $100 up to a large models that cover 750 square feet for around $500. Units come with easy access for cleaning, remotes, fan and direction controls. Some have the ability to add ice for further cooling.
The number one complaint customers have about portable coolers is that they do not cool as well or as thoroughly as a traditional air conditioner. Capacity is limited (area cooled) and degree drop as well. For this reason, customers should be cautious about their expectations from any evaporative cooler. Negative comments included the need to clean to prevent smells, the need to add water frequently, an inability to blow cool air more than a few feet and the lack of truly cold air.10 Customers with hard water complained about scale build up.
Positives revolve around price, portability and adding humidity in a dry environment. Several customers mentioned that it helped their asthma and breathing while sleeping.
It appears that before purchase, consumers would do well to see a unit in use. This will allow them to better appreciate both what an evaporative cooler can do and what it cannot do. Over and over, comments remarked, "This is not an air conditioner."