Outstanding Air Purifier

Filter: The filter on the IQAir will filter microns to 0.003, which is the size of viruses. Most HEPA filters air at about 0.3 microns, which some could argue is all most of us need in our homes. If you run the machine about 10 hours a day at setting 3 you should will at least get 2 years out of the filter. The filter change stated is 2-4 years. The pre-filter last 6-18 months and if you vacuum it once and a while you should get good use from it. Having a good filter in your furnace will also keep the pre-filter cleaner, I use a merv 12 in the furnace and change it every 3 months. Going rate for the HEPA filter is about 189 and the pre-filter is about 70.

Controls: This machine has a very detailed menu (reminds me of a printer menu). I read the owners manual and was up and running in about 15 minutes. The menu will tell you when its time to change the filters. The 6 air fan speeds are for the most part quiet at lower settings but can be a little loud at the highest ones (44 dBA on low, 72 dBA on high). You can also program it to automatically change settings.

Quality: IQAir makes medical grade equipment, such as setting up a positive pressure room for those with immune compromised systems. The unit is totally sealed, if air leaks are a concern. When you place a particle meter (measures the particles in a room) up to the out vent on this machine you will get zero. What you have is totally filtered air coming out. Many other machine leak around there filters (not sealed good) though for the general person this may not matter all that much.

Concept: When thinking of a HEPA device, remember that your goal is reduce the number of particles in your air. Ways to increase the quality of your air is to get a good furnace/air conditioning filter with a high merv rating. This will capture 90+ % of particles in your air, thus letting your IQAir take care of the real small stuff. You also can increase efficiency by turning on your ceiling fan or keeping some fans on low (I like Vernado fans). Even a lower end machine will eventually reduce the overall particles in your room by applying these principles.

Air Flow: The speed settings offer the following CFM (cubic feet per minute): 45 75 115 150 180 240. Beware that some companies really inflate these rates, but not IQAir. From what I have read they are very precise and non-deceiving about what their unit can do. They test each unit and certify it before it leaves the factory. The fan uses ball barings and is balanced, which usually means its going to  last for years (there is a five year warranty).

Overall: This is a very high quality air purifier that can purify spaces up to 900 sq ft, though most recommend using it in spaces about 450 sq ft to get about 4 air changes an hour. There are certainly a number of air cleaners that are less expensive, but if you are looking for a quality machine that will last for years the IQAir should work for you.

Update: Have used this machine for a couple of years and it is fantastik. The filters last a long time because unlike other brands IQ Air traps 90% of particles in their prefilter...which allows much longer life from the HEPA filter. The only flaw I can state is that the caster wheels are a little cheap and one falls out when the unit is picked up. I used to take several allergy medications and now very seldom do I need them. At this point I am happy with the purchase.