Review: Air-O-Swiss Ultrasonic Humidifier AOS 7144

Ah, Spring is here. And along with it comes its palate of blooming colors: yellow Daffodils, green grass, and red noses from the explosion of allergies that arrives with a rapidly rising pollen count. While nature's bounty causes allergies and colds this time of year, so does the dry indoor air. But relief can be yours just by putting some moisture in your lungs.

The AOS 7144 humidifier is such a contraption. A pre-heating button sets the mist when it reaches a temp of 104o F which is close to human body and won't heat up a room on a warm spring day. Without the pre-heat button on, mist comes out cooler and actually acts feels a bit like a faux air-conditioner. The mist-o-fier humidifies rooms up to 650 square feet, as long as windows are shut and the unit is not stationed near a heat vent.

In our tests, we set the target humidity to 50 percent (the optimum humidity according to medical experts is between 40 and 60 percent). Using Oregon Scientific's desktop WeatherNow and another humidity gauge, we confirmed the accuracy of moisture content as we watched the front LED window climb from 39% to 50% in less than 30 minutes and then maintain the level by shooting out mist in periodic bursts. The 3.5 gallon water reservoir lasted for over 36 hours without a refill.

A problem that plagues many humidifiers is the lime scale and mineral residues that build up from the tap water used to fill them. Air-O-Swiss eliminates that with its replaceable demineralization cartridge. Equally yucky is the microbial growth that accumulates in the water basin, especially when the appliance is not used for some time. The AOS 7144 incorporates a patented Ionic Silver Stick whose aqueous silver ions inhibit bacterial growth for about a year. In addition the high-frequency vibrations that produce the mist also destroy most bacteria and viruses, according to Air-O-Swiss.

We particularly liked the one-click sleep mode which pre-determines the correct evening humidity level and shoots warm mist for a pre-set 8 hours. And because it runs absolutely silent, this puppy is great for use in a bedroom. Not so wonderful is the somewhat clumsy method of refilling the water tank, which involves unscrewing the demineralization cartridge and filling the tank upside down. But there is some truth to how proper humidification relieves red eyes and raw throats. After running the AOS 7144 for a week, our previous issues with puffy itchy ocular cavities and phlegmy throats subsided. Gives a new reason to the request "Play Misty for Me."