do those air purifiers work?

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Looney

Lifer
Jun 13, 2000
21,938
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Yeah i know... i've been searching on Amazon for Hepa filters, but i can't find anything on how long they typically lasts. I thought it was only 2-3 month per filter, but a friend just told me she only changes hers once a year.... i don't know if it's just her model, or if that's typical of how long they last. I saw some of them have UV lights that kill microscopic bacteria too... i remember seeing a show on people that install the UV lights in their furnance or ventillation system, and it supposedly help get rid of things like mold.
 

kh3443

Senior member
May 31, 2002
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I got one for my room because I smoke and it works great. My parent's home got one too.
 

Staples

Diamond Member
Oct 28, 2001
4,953
119
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I have had an Ionic Breeze for a year or more and all it seems to do as far as what I throw at it is pick up dust from the air. I don't smoke or have a cat but if I did, I'd probably see more of a result. I have to clean it like every two weeks because it starts making noise. other than that, it is silent.
 

0roo0roo

No Lifer
Sep 21, 2002
64,795
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dig out last years consumer reports tests. ionic breeze is dead last. it spits out toxic ozone to boot.

 

Staples

Diamond Member
Oct 28, 2001
4,953
119
106
And if you decide to get one, get one off Ebay. You can get one $100+ cheaper however they are probably refurbs. Like I said, all mine seems to pick up is dust and since so little air passes through it compared to a fan, I am possitive fan/filter ones work a lot better however I have heard things like you are only supposed to run those things for one hour a week and then they should last 6 months. I am sure the filters are not cheap at all.
 

erikiksaz

Diamond Member
Nov 3, 1999
5,486
0
76
Originally posted by: 0roo0roo
dig out last years consumer reports tests. ionic breeze is dead last. it spits out toxic ozone to boot.

w0ah w0ah, stop right there! So what came in first, second, ... ?
 

Looney

Lifer
Jun 13, 2000
21,938
5
0
Originally posted by: 0roo0roo
dig out last years consumer reports tests. ionic breeze is dead last. it spits out toxic ozone to boot.

Wow, it appears you're right.

I looked my model up too, and it's a Kenmore Electrostatic air purifier. But i hate cleaning the thing, so i might pick up a Hepa... depending on how often i need to replace the filter... which i still can't find the answer for!

Does nobody here own one? And how often do you change your filter?
 

0roo0roo

No Lifer
Sep 21, 2002
64,795
84
91
Originally posted by: erikiksaz
Originally posted by: 0roo0roo
dig out last years consumer reports tests. ionic breeze is dead last. it spits out toxic ozone to boot.

w0ah w0ah, stop right there! So what came in first, second, ... ?

lol i don't remember:) since i'm not in the market for one i only remember the ionic breeze being last because it was interesting:) most anything with a fan beats the pants off it obviously:p
 

tcsenter

Lifer
Sep 7, 2001
18,949
575
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dig out last years consumer reports tests. ionic breeze is dead last. it spits out toxic ozone to boot.
There are probably a dozen threads on air filters/purifiers and the Ionic Breeze specifically in the archives.

But you are being too nice. Consumer Reports said the Ionic Breeze Quadra had the worst performance of any air filtration product they have ever tested in the 10+ years CR has been testing household air cleaner/purifier products.

The Friedrich C-90A has earned top honors in CRs tests many times, though its filtration mechanism is primarily electrostatic, it combines a mechanical 'pre-filter' for larger particles, and an activated charcoal filter for odors/VOCs.

A good electrostatic cleaner like the C-90A can be a very good air cleaner with high efficiency, but the electrostatic plates must be kept clean because its filtration efficiency rapidly declines as the plates become saturated with dirt/dust/particles. Electrostatic products are high maintenance for this reason, it must be kept substantially clean to do its job.

As good as electrostatic filters can be, none compare with HEPA in terms of filtration efficiency and low maintenance. The filtration efficiency of HEPA filters actually increase as the filter becomes dirty, until the filter is so saturated that air can no longer pass through at reasonable rates.

So why has the C-90A consistently taken top honors over all tested HEPA filters?

Because the testing methods used by CR do not test the products long enough to bring-out the weakness of electrostatic products nor the strengths of HEPA products.

CR Labs fills a sealed chamber of known volume with contaminants of a known concentration. They then test to see how long it takes each product to 'clear' the air to a specified level of clearance measured by, among other devices, a spectrometer. The time it takes for each product to achieve the same level of room clearance is the 'clearance rate'.

Because HEPA uses a mechanical filtration matrix, air flow through HEPA is obstructed as it must find its way through the microchannels of the matrix. An electrostatic mechanism is relatively unobstructed and can achieve higher exchange/flow rates, thus clearing the room 'faster', not necessarily 'more'.

The room clearance test only takes a couple hours for the best cleaners, yet air cleaners will not be used in your home for just a couple hours then boxed-up forever. It will have to exchange the air in the room hundreds or thousands of times, over the course of months or years. CR Labs also doesn't take maintenance into account as weighing for or against any product.

There is a lot of misrepresentation in the marketing of air purifiers (surprise). Some companies pushing electrostatic cleaners, including Friedrich, claim that HEPA cannot filter particles smaller than .3 micron. This is false. HEPA by definition is able to achieve a minimum 99.97% filtration efficiency @ .3 microns. Companies pushing competing products have interpreted this to mean that HEPA efficiency declines as particles smaller than .3 microns are encountered, when in fact the opposite is actually true.

A combination of principles and mechanisms are at work in a HEPA filter (or any mechanical filter); straining/seiving, inertial impaction, interception by Van der Waals forces, and diffusion by Brownian Motion are the main principles/actions.

Particles are influenced (and captured) through one or more of these principles depending on their size, density, velocity, and ionization state. There is an overlap between most of these principles where a particle may be equally influenced by more than one principle.

By some arbitrary feat of physics, there is a median particle size which does not readily lend itself to influence by any of these mechanisms or principles and thus is the most difficult to capture. That median particle size is .3 microns, or roughly between .25 and .35 microns.

If you want to built the most effective filter known to man, you find the most difficult particle to capture, then build a filter whose definitive performance standard is to capture that median particle size.

The 99.97% filtration efficiency of a HEPA filter at .3 microns (mil-spec DOP/HEPA test) is THE WORST CASE SCENARIO because .3 microns is the most difficult particle size to capture for any mechanical filter. Particles both larger and smaller than .3 microns are filtered at a virtual 100% efficiency because they readily lend themselves to influence by one or more of the aforementioned principles.

HEPA filters remain effective until you approach the particle size of VOCs, or around .001 microns. No mechanical or electrostatic filter is effective at these extremely small sub-micron sizes and chemical means must be employed.
 

FeathersMcGraw

Diamond Member
Oct 17, 2001
4,041
1
0
Originally posted by: Moralpanic
Yeah i know... i've been searching on Amazon for Hepa filters, but i can't find anything on how long they typically lasts. I thought it was only 2-3 month per filter, but a friend just told me she only changes hers once a year...

Or she's just not following a proper maintenance schedule.

If a HEPA filter is doing its job effectively, it's going to need to be replaced every three months or so. There might be variances depending on how clean you keep your environment, but I've always been told that if your air filter looks dirty, you've waited too long to replace it.
 

Kelemvor

Lifer
May 23, 2002
16,928
8
81
THey work just fine. I have one and the dirt I wipe off that thing every week is nasty. However, some people don't know the best way to get them. NEVER order them at a SharperImage store or catalog. Go to their website and go to their auction site. You can get one (get code YYY, not ZZZ, ZZZ is broken and fixed, YYY is jsut returned). Still come with the full 3 year warranty and everything and you get it for less than half price.

I got one and got one for my wfe's parents and they work great.

Sharper Image Auction
 

Kelemvor

Lifer
May 23, 2002
16,928
8
81
Originally posted by: Moralpanic
Yeah i know... i've been searching on Amazon for Hepa filters, but i can't find anything on how long they typically lasts. I thought it was only 2-3 month per filter, but a friend just told me she only changes hers once a year.... i don't know if it's just her model, or if that's typical of how long they last. I saw some of them have UV lights that kill microscopic bacteria too... i remember seeing a show on people that install the UV lights in their furnance or ventillation system, and it supposedly help get rid of things like mold.

It depends on your house. We have an air filterer thing with a HEPA filter and a Pre-Filter. THe HEPA filter was copmletely black and useless after about a month or so but that's because I have 3 cats and a dog. We just took the HEPA filter out ad don't use it. Still gets all the pet fur out of the house and the Ionic Breeze helps with smaller stuff in the bedroom.

But I think under "normal" circumstances it should last between 6 months and a year.
 

tcsenter

Lifer
Sep 7, 2001
18,949
575
126
Originally posted by: RossMAN
Damn that Friedrich C90A goes for $499!
Yep, unless you can find some coupon codes, instant discounts, and rebates. :D

I prefer Austin Air products, myself. Actually, I prefer 'whole house' filtration products that are installed in your central HVAC. Those negative ionizers coupled with the 3M high efficiency fiber furnace filters work pretty well.
 

KokomoGST

Diamond Member
Nov 13, 2001
3,758
0
0
Originally posted by: RossMAN
You either love or hate the Ionic Breeze, I just happen to hate it, dunno why :D

Mebbe because it costs too much and kinda sucks? Heck, even Honeywell sells the ghey Environizer for less through the RatShack. It still sucks monkey butt though. All the ionics produce ozone within a few feet of the unit which is bad for asthmatics and people with respiratory problems.
 

tcsenter

Lifer
Sep 7, 2001
18,949
575
126
Originally posted by: RossMAN
You either love or hate the Ionic Breeze, I just happen to hate it, dunno why :D
People love it because they don't know any better...kinda like people who love AOL. lol!

While quiet operation is definitely a plus, there are HEPA units out there which are quite reasonable in the operating decibel department, cost less than the Ionic Breeze, have a higher filtration efficiency, don't require nearly as much maintenance, and will clear a room faster than the Ionic Breeze.

As I said, people love the Ionic Breeze because they don't know any better.


 

RossMAN

Grand Nagus
Feb 24, 2000
79,083
456
136
Originally posted by: tcsenter
Originally posted by: RossMAN
Damn that Friedrich C90A goes for $499!
Yep, unless you can find some coupon codes, instant discounts, and rebates. :D

I prefer Austin Air products, myself. Actually, I prefer 'whole house' filtration products that are installed in your central HVAC. Those negative ionizers coupled with the 3M high efficiency fiber furnace filters work pretty well.

Are there any comparable air purifiers in the $300 range you'd recommend?
 

DBL

Platinum Member
Mar 23, 2001
2,637
0
0
I have a BlueAir 501 that I purchased for $388, which I can recommend. It's a bit pricey, although they do make some other models. I've been running it for about a week and it has significantly reduced the amount of dust in my apartment. I moved in about 6 weeks ago and previously had the wood floors sanded and refinished which created a lot of dust.
 

tcsenter

Lifer
Sep 7, 2001
18,949
575
126
Are there any comparable air purifiers in the $300 range you'd recommend?
There probably are, but its been a couple years since I've been in the market for an air purifier. The Friedrich C-90A can be found for less than $499, which is the MSRP. In fact, this company is selling the Friedrich C-90A with four carbon filters for $499.95 after discounts (fill out their survey and get a e-coupon discount). Right up your alley!

My parents have the Honeywell Envirocare 63500 and my sister has the Honeywell Envirocare 13520. They're a bit noisy unless they're set to the the lowest fan setting and I'm not fond of the Honeywell intake design because the exterior of the unit becomes completely covered in dust/dirt so you have to wipe it clean or vacuum it every week. But they work well and the filters are affordable. I'm not sure if either of those models are still made, they may have been replaced by newer units.

Hunter makes a few good models, like the QuietFlo 400 HEPA Purifier.

Austin Air and IQAir are like the Mercedes of air purifiers. Both make commercial and medical grade air purifiers. I've seen some Austin Air home units on sale for around $300.

Compare Clean Air Delivery Rates (CADR), room air-exchanges per hour, prices, operating decibels, filter replacement costs, etc.

Some additional places to shop/browse:

Noble Winds

Air Cleaners.org

I'm sure there are others, but that's a start.