Inside CR Test Labs: Maintaining an air purifier

How well you maintain your air purifier will directly affect its performance over time

Do you remember the last time you cleaned the filter in your range hood or replaced the filter in your furnace or air conditioner? If no, you’re not alone. As part of our testing for “Filtering the Claims,” we wanted to see how air-cleaning performance would changes as an air purifier’s cleaning media became loaded with dust, smoke, and other airborne particles. We also hoped to determine if you  need to replace filters as manufacturers suggest or if doing so is a waste of money.

To measure how cleaning performance changes over time, we tested the Friedrich C-90B plate-type electrostatic precipitator, or EP, air purifier and the Whirlpool Whispure AP45030S and IQAir HealthPro Plus HEPA-filter models. We ran these air purifiers nonstop for one year in a very large commercial space whose air we expected to contain dust and smoke particles.

We also rearranged the devices in the space to ensure each machine experienced the same conditions. And throughout the year at regular intervals, we brought the purifiers back to our labs to gauge their cleaning performance.

While the performance of the two HEPA models declined gradually and at a similar rate, that of the Friedrich (shown) fell more abruptly—about 20 percent in one month. It took the entire year, including not changing the prefilters at the manufacturers’ recommended intervals, for the HEPA models to decline that much.

However, because the Friedrich’s initial performance was the best of this group, after a month its absolute performance, indicated by its clean-air-delivery rate, or CADR, was still higher than that of the IQAir when new—265 compared with 237. It took about another month without cleaning its plates before the Friedrich’s CADR dropped below 237. What’s more, after we cleaned its prefilter and collection plates, the Friedrich saw its CADR return to its original high value of 335, confirming the importance of maintenance.

The bottom line: You need to maintain your air purifier if you expect it to keep cleaning the air in your home. Our testing supports the typical maintenance recommendations from manufacturers. Note that our testing also shows that plate-type EPs generally require more-frequent filter cleaning than filter-based purifiers.

But you’ll likely spend more to maintain and run a filter-type purifier than you will for an electrostatic precipitator since the former type normally uses replacement filters and consumes more electricity.

Still, if you’re unlikely to perform the necessary maintenance, opt for a filter-type purifier, which we consider your best choice overall because it cleans the air without producing ozone. Research is increasingly warning against adding ozone to indoor air, though more studies need to be conducted to determine the effects of low-level ozone exposure on humans.—Ed Perratore

Essential information: Our Ratings of room and whole-house air purifiers include annual costs for energy and filters or other media. Read our advice on how to improve the air quality in your home without an air purifier.

Comments

[Bill Unyi]

You do not need to be a rocket scientist to maintain your air purifier. The biggest thing that people neglect is changing their filters on a regular basis. You wouldn't go 10,000 miles on an oil filter for your car and the same goes for filters for your air purifier.

It's nice when the air purifier has filter change indicator lights, but not all do. Keep these tips in mind:

1. You can maximize the life of your filter by only using the air purifier when needed. Do not leave the air purifier on 24 hours a day unless you have to. If the manufacturer says that you can get 5 years from their HEPA filter, use air purifier as needed and you can get 5 years from the filter. At the 5 year mark, replace the filter and start all over again. Just like you do for your car's oil filter.

2. Realize that if you are going to leave the air purifier on for 24 hours a day, you are going to cut your filter life in half. If a manufacturer gives 5 years of life on their HEPA filter and the air purifier is left on 24 hours a day, you will only get 2-3 years from the filter. This is due to the fact that the air purifier is filtering constantly and not getting a break.

3. Make sure to replace Prefilters and Postfilters regularly. This is usually the first line of defense for most air purifiers and these filters capture the largest of the air pollutants. Clean and replace often. Usually every 6 months or once a year. Washable filters may give you a little more time, but they will eventually lose their effectiveness after a few washings.

4. Try to keep dust off the machine by wiping it down with a wet towel at least once a month. This will help with keeping the air purifier clean and able to purifier the air more effectively.

Hope these tips help and keep breathing cleaner air with your air purifier.

[troy]

Have a problem about Home Air cleaners, Air purifiers, and also home improvement.. i had an answer..

check this out: http://homefixfree.com/index.html

[Ed]

This article mentions the top-rated, "quick-pick" Whirlpool Whispure AP45030S.

Sadly, however, it appears Whirlpool has pulled out of the room filter market. This product doesn't seem to be available and a glance at Whirlpool's site shows that while they sell replacement filters for it, they now produce do whole-house air cleaning solutions.

[Ed]

This article mentions the top-rated, "quick-pick" Whirlpool Whispure AP45030S.

Sadly, however, it appears Whirlpool has pulled out of the room filter market. This product doesn't seem to be available and a glance at Whirlpool's site shows that while they sell replacement filters for it, they now only produce whole-house air cleaning solutions.

[mark fera]

want a gerat hepa air filter for less than $50.00. 1 buy a cheep box fan for under $15.00. 2 buy a roll of duct tape. 3. buy a 20x20" air replacement filter( the very best are under $20.00.) tape the air filter to the back of the fan. make sure you seal it all the way around. Turn the fan on. this really works like a charm.