Review: The Air-O-Swiss 7135 Humidifier

Screen Shot 2013-11-13 at 10.38.40 PM

Let’s get this decade of my life started off right. Let me tell you about my high-tech humidifier.

AoS7135The unit in question is the Air-O-Swiss 7135. It’s an ultrasonic model with a replaceable demineralization cartridge impregnated with silver ions to impede bacterial growth. It has programmable controls and a built-in humidistat, so you can set it to either run for a given duration, or to turn itself on and off to maintain a desired percent humidity. It also has an optional preheater so that the mist doesn’t lower the ambient temperature of the room.

I’ve been loving it. Once the weather here changed and I had to turn on the heat in my house I was waking up with sore throats, aching sinuses, nostrils that felt like they’d been packed with sand while I slept. I got nosebleeds, an infection, lost my voice. Things got better when I went out and bought a hot mist (boiling) humidifier as a stopgap measure, but that raised the humidity in my room so high that it got musty, and on very cold nights water would condense on the windows and exterior walls. With the Air-O-Swiss, though, I can watch the hygrometer display and see it adjusting its output to maintain the humidity where I want it. It oscillates, but my experience is that it manages to keep things stable plus or minus around three percent. Since it’s cool/warm mist, I can set it up near where I sleep and have the occasional lovely and ominous curl of mist roll silently over the bed and disappear in front of me like a ghost. I’m sleeping better, and waking up better, than I have in a long time.

transducer plateUltrasonic humidifiers work by using a transducer to physically separate water molecules into a mist. This makes it quieter than models that boil water, or evaporative humidifiers that use a fan to blow air through a wick. The downside is that since the mist is being mechanically created rather than produced through a chemical process like evaporation or boiling, the mechanism is indiscriminate about what it aerosolizes. The transducer is happy to vibrate minerals, microbes, whatever happens to be in the water into the air for me to breathe. There are varieties of pneumonitis that are actually known as humidifier lung. As I’m on immunosuppressive drugs, that makes keeping the thing clean of particular importance. Fortunately, this model makes it easy. It comes with a solvent and has an indicator light for monthly cleanings, but I do it more often than that. About every three days, actually, as recommended by the Mayo clinic. The mouth of the tank is wide enough to allow quick and easy water changes, and the base mostly easily-scrubbable flat surfaces. It even comes with a little brush for getting scale, which can harbor bacteria, off the transducer plate. So far, though, the filtration and demineralization features are good enough that in a week of operation I haven’t noticed any of the white dust that’s typical of ultrasonic humidifiers. Assuming I don’t ironically die of Legionnaires’ disease in the next couple of months, I’m very pleased with everything about the device.

The bad news: it costs $180. That’s on the very pricey side for a humidifier, and if that matters you could probably buy a less expensive one, a hygrometer, and a timer switch from a hardware store for less than the Air-O-Swiss. But if the all-in-one convenience is valuable to you, or you’re having a birthday and willing to ask for the kind of thing that you want but would never buy for yourself, then the Air-O-Swiss is great.

1 Comment

Add yours →

  1. Note from the future: it eventually did start producing the white dust that is endemic to ultrasonic humidifiers.

Leave a Reply