I live in Central Texas, which means that Im subjected to various types of pollen allergies for at least half the year. I am not severely allergic, but its bad enough that I need to take some kind of allergy medicine to minimize allergic symptoms. Ive purchased small air cleaners before and although they help in smaller rooms, they dont perform as well in larger rooms.
A while back, I decided to buy a bigger air cleaner for my living room. I was looking for a reasonably priced model that used true HEPA filters, had a CADR rating over 100, and had an activated carbon filter for odor control. After much research I decided to purchase a Holmes HAP1625 Air Purifier (this model is identical to the Holmes HAP725, HAP726).
TrueHEPA
HEPA stands for High Efficiency Particulate Arrestance. It was developed during WWII to protect Atomic Energy Commission researchers from radioactive dust in the air. Real HEPA filters can filter up to 99.97% of particles 0.3 microns or larger under optimal conditions. A micron is one millionth of a meter. A human hair averages is around 70 microns in diameter, pollen is over 5 microns in size, and smoke is even smaller.
I am covering this subject because some air cleaners on the market use HEPA-type filters. These are not true HEPA filters and most are advertised to filter 99% of particles 1 micron or larger. In all honesty, this is good enough for most people with pollen and mold allergies, although people wishing to filter out pet dander, dust and smoke will need a true HEPA filter.
I probably dont need an air purifier with a true HEPA filter, but since I have rather eccentric phobias toward microscopic entities (and Im a bit of a nitpicker), I wanted a true HEPA filter.
Controls and Basic Use
All the controls are push-buttons. There is an on-off button and speed control button. There are four fan speeds.
Air Cleaning Performance
It is difficult for me to statistically measure the performance of this machine. I dont own a meter measuring airborne particulate matter so I cant verify that the HEPA filter is really filtering 99.97% or not. I read a study that states that most air cleaners dont perform up to the full capabilities of HEPA filters due to issues of build quality, filter seal quality, fan strength, etc. For this product, I can only measure performance based on my personal judgment and the severity of my allergic reactions.
This air cleaner was rated by the manufacturer to clean a room up to 256 sq. feet. I initially placed this air cleaner in my living room, which is 16x13 with a 9 foot vaulted ceiling. It is open to a small dining room and partially open to my kitchen. I ran the machine 24/7 on the number two setting. After a full day of operation, the odors in the room reduced noticeably and my allergies improved a bit. The carbon pre-filter caught a lot of dust and was covered in a thin layer within a week. After a week of use, I estimate that my allergies were reduced maybe 30-40%. Thats much better than the small, tabletop air cleaner I previously used, but not as good as Id hoped.
After three months, I moved the air cleaner to my bedroom because my allergies were affecting my sleep. After a week of running the unit continuously (mostly at setting two; I used setting one at night to reduce noise), my allergies were reduced 50-60% and I slept better with little or no interruptions. I think the performance of this unit improved because my bedroom is smaller than my living room (14x11, 8 foot ceiling) and there are no adjoining rooms, so the machine had less air to clean.
Other Performance Issues
If youre concerned about noise, youre not going to like this air cleaner. Even at its lowest setting, this machine is fairly loud; similar to a box fan at medium speed. I can sleep at the lowest setting, but it might be too loud for people who prefer to sleep in quiet settings. The highest setting is quite loud; similar to a kitchen hood fan at high speed.
The air cleaner is slim and reasonably attractive in design. It fits flush against a wall and out of the way. This machine does not have an ionizer.
Filter Replacement
The air cleaner has two indicator lights, one for the HEPA filters and one for the carbon filters. So far, the carbon filter indicator has turned on every four months. Im not sure these indicator lights are dependable and its probably best to stick to the manufacturers suggestion on filter replacement times (once a year for the HEPA filters, once every three months for the carbon filters).
The air cleaner takes two HEPA filters and two carbon filters. Both filter types are easy to find at Wal-Mart or Target. Filter replacement prices are very reasonable with a two-pack HEPA filter priced just under $40 and a four-pack carbon filter priced at around $10.
Final Thought
There are probably some air purifier purists out there who will dismiss me for giving a Holmes air cleaner a decent review. The fact is this air cleaner is an average performer at best, and there are better air purifiers available. The big issue for me is price; these high performance air purifiers are very costly. I would love to own an IQAir, Austin Air, or AllerAir air purifier, but these units cost upward of $400 to over $1000 each, and annual filter replacement costs can be over $100. Because I dont have severe allergies, I find it difficult to justify the high costs of owning these arguably superior machines.