OT: Ionize setting on an air filter...

[narf poit chez BOOM]

...Is it actually worth anything? I got a new one with this, but my room seems worse for allergies since I got it than with the last one.

[Baron Munchausen]

The allergy problem is probably caused by the filter not working rather than the ionizer feature.

Ionizers are throwing out 'negative' ions, meaning they carry some extra electrons. This is the same effect as you get when it rains. The falling rain generates 'static' electricity (which is why rain is often accompanied by lightning) and charges the air. One effect of this is to 'capture' lots of dust and finer particles in the air. In the Great Outdoors all this means is 'fresh air' but indoors it means dust & odors clinging to walls, furniture, and everything else as those charged ions carrying all that dust have to go somewhere. Outdoors it doesn't matter if they stick to the trees & ground of course.

CRTs and many other electronic parts throw off a lot of positive ions, btw. Which means that the negative ions tend to be attracted to electronics, and can clog up your electronics much faster than would normally occur. Ionizers are hard on electronics. So it's entirely possible that the dust is coming to meet you as you sit in front of your computer. That could also be why the room seems 'worse' with the ionizer.

[Slick]

Sometimes these ionizers can create ozone (O3) out of the normal oxygen (O2) in the air. Trace amounts (i.e. less than 0.05 ppm) are not normally a problem, but in an enclosed room it can build up a little, and if you happen to be especially sensitive to it, ozone can cause or exacerbate respiratory problems.

[narf poit chez BOOM]

It's not in the computer room. However, given that, I think I'll turn it off. I'd rather have the stuff in the filter than on the walls, where it'll fall off...

[Slick]

Normally an ionizer is accompanied by some kind of electrostatic precipitator (could be called something different), but the ionizer basically charges up impurities in the air and the precipitator captures them by attracting them to charged plates - an efficient way of cleaning the air.

[rdouglass]

Slick said:
Sometimes these ionizers can create ozone (O3) out of the normal oxygen (O2) in the air.

That's exactly what they're supposed to do. Just as mentioned, it's supposed to be in small quantites. Ozone can and will kill many / most molds and mildews so that's why its beneficial to many alergy sufferers.

Also, ionization aids particulates (smoke, dust, dander, etc.) to collect with each other and fall out of suspension in the air. (You may and should notice dusty areas in front of the ionizer itself.)

I have one that uses UV light to kill bacteria as well. Hopefully your's has adjustments 'cause too much ozone can leave you with headaches, dry nose, etc. and is generally not healthy. However, I have found that I play with the adjustments until it smells faintly (very faintly) like after a thunderstorm (as previously mentioned) that seems to be the optimal setting for me.

My wife has numerous alergies (and my 6 year old seems to be developing them as well - are they hereditary?) but that combination (ionizer and UV) seems to work wonders for them. I am quite satisfied that most if not all of their (air filter people) claims are quite true.

[Slick]

Not all ionizers are intended to create ozone. The well-publicized "Ionic Breeze" from Sharper Image uses the process I described to clean the air. It creates small amounts of ozone as a byproduct; which is either negligible or a health hazard, depending on which review you read.

[narf poit chez BOOM]

It's only got off and on for the ionizer.