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Mist cooling systems offer outdoor A/C

Whew, it’s hot out there. Inside our homes, we have the option of turning on the air conditioning, but what about outside?

With the trend toward outdoor living, it’s important to find a way to beat the heat so that you can enjoy grilling, dining, partying or plain old relaxing in your backyard — even when the mercury soars. Mist cooling just might fill the bill.

What is Mist Cooling?

Mist cooling works to lower the surrounding air temperature by a process of evaporation. A mist line, consisting of polyvinyl chloride pipe installed 8 to 10 feet above ground level, sprays out minuscule water droplets that flash evaporate instantly.

The energy exchange involved in this flash evaporation cools the surrounding air effectively, reducing temperatures in the vicinity by as much as 35 degrees Fahrenheit on very hot days. Residential systems range in complexity from a small portable mister fan to a powerful misting device designed to be hardwired in place. Huge misting towers are available for commercial use.

Is Mist Cooling EcoFriendly?

Misting is a green method of cooling. Unlike a conventional air conditioner, the system uses only water to lower the temperature and as a result, doesn’t give off any dangerous greenhouse gases, such as ammonia, chlorofluorocarbons or sulfur dioxide.

Mist cooling will benefit your family members and guests who suffer from allergies or other breathing problems by filtering out airborne dust and pollen. It also is a natural, cruelty-free deterrent to flying insect pests like wasps.

Misting systems do consume a certain amount of water, but it is only a fraction of the amount required to produce hydroelectricity sufficient to power an air conditioner. Also, an experienced heating ventilation and air conditioning technician can install the system so it will conserve water by doubling as irrigation for a raised-bed or container garden on your patio or deck.

Other Advantages

Mist cooling systems are simple to set up and to keep in good repair, with only two moving parts — the pump and the fan’s motor. For maintenance, basically all you need to do is ensure a steady water supply and clean out the mister occasionally.

The system is energy-efficient and inexpensive to run, at about only one-eighth of the price of using your air conditioning. Cost to install a mist cooling system is also relatively low compared with A/C. The pipe of a hardwired misting system may be winterized against freezing and bursting, making it safe to be left in place throughout the year.


Mist cooling is best suited to regions with a very hot, dry climate in summer (like the Las Vegas Valley). At more moderate temperatures, or when the outdoor air is already quite humid, this type of cooling is not as effective. What’s more, the humidity that a mist cooler produces damage your wooden deck or to electronic equipment including items such as smartphones or other.

If it is not regularly cleaned and maintained, a mist cooling system can become a health hazard, acting as a breeding ground for mosquitoes, mold and mildew, and Legionella bacteria, which can cause such illnesses as Legionnaire’s disease and Pontiac fever.

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