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Most air purifiers only remove solid airborne particles of a certain size, such as dust, pollen and pet dander. Not that there’s anything wrong with that — trapping these common pollutants is what these appliances are expected to do. However, these days that is just the bare minimum.
From appliances that can absorb unpleasant smells and humidify your air to air purifiers that charge your phone and diffuse essential oils, brands constantly try to outdo each other with new, exciting products. But the defining feature of the best air purifiers remains the same — the ability to remove the tiniest of airborne contaminants. Increasingly, this includes viruses, bacteria and yeasts. The Blueair Classic Pro CP7i is a perfect example of this trend. It is the first air purifier with High-Intensity Narrow Spectrum (HINS) lighting.
This relatively new technology uses violet-blue light with a wavelength of 405 nm (nanometers) to help remove minuscule germs that linger in the air. HINS generates free radicals (highly reactive molecules with unpaired electrons) that tear through the chemical structure of germs captured on the air filter, thus preventing them from spreading.
In that sense, it works similarly to UV light — although it is not as effective. However, HINS is also safer than UV light, because it does not carry the same exposure risks (such as DNA damage, for example), according to a 2014 review published in The Journal of Hospital Infection.
This feature alone could earn the Blueair Classic Pro CP7i a spot in our guide to the best air purifiers for allergies. But how does this air purifier perform in practice? We put it through its paces to find out what it is truly capable of.
Blueair Classic Pro CP7i air purifier review
Blueair Classic Pro CP7i: Design
- Big, heavy and expensive
- Bright, easy-to-read LCD screen
- Air inlets at the back of the unit
Key specs
Dimensions (in): 19.7 x 9.9 x 23.6 (W x D x H)
Dimensions (cm): 50 x 25 x 60 (W x D x H)
Weight: 32 lbs (14.5 kg)
Coverage: Up to 1,400 square feet (130 square meters)
CADR: from 231 CFM (dust) to 393 CFM (smoke)
Fan speeds: Four
Auto mode: Yes
Max noise: 55 dB
Ionizer: No
Smart features: App and voice control
Energy Star-certified: Yes
Warranty: 5-year limited warranty
The Blueair Classic Pro CP7i did not make a good first impression on us. With almost 24 inches (60 cm) in height, 20 inches (50 cm) in width and a bland, boxy design, it looks more like a desktop computer than an air-cleaning appliance. It is heavy, too. The Blueair Classic Pro CP7i weighs a considerable 32 lbs (14.5 kg), and even though it comes with a pair of wheels at the bottom and a small handle at the top of the unit, this beastly machine is still tricky to move around.
This air purifier is not just big; it also takes up plenty of space. The Blueair Classic Pro CP7i has one huge air inlet at the back of the unit and two smaller air outlets located on the sides. This means you need to leave some room around it for the air to circulate properly. As a result, this air purifier may not be the best option for crowded rooms or small apartments.
On the plus side, the Blueair Classic Pro CP7i is built like a tank. While we can’t vouch for its durability — we only tested it for about a month — it seems stable and resistant to wear-and-tear damage. We reckon this air purifier could easily survive an encounter with playful children or curious pets. Plus, it comes with a 5-year warranty.
We also liked its control panel. The icons are large and intuitive to use, and the color-coded LCD screen makes it easy to gauge air quality at a glance. Blueair did a good job there. Most air purifiers come with displays so small you have to strain your eyes to see anything. With the CP7i, however, everything is clear and easy to read.
However, all of this high quality comes at a steep price. The Blueair Classic Pro CP7i costs $699.99, making it one of the most expensive air purifiers we have tested. In addition, a replacement filter costs $99.99 and even considering its one-year lifetime, it is more than you would typically pay for a HEPA filter. On the other hand, this air purifier is Energy Star certified, so it will not eat much into your energy bill. For a machine of this size and power, this is an undeniable advantage.
Blueair Classic Pro CP7i: Features
- App and voice control
- In-depth air quality readings
- Four fan speeds
- Auto, eco and night modes
Feature-wise, the Blueair Classic Pro CP7i does not disappoint. We were particularly impressed by its exceptionally detailed air quality measurements. This air purifier displays the exact levels of 1-, 2.5- and 10-micron particles in the indoor air, going above and beyond the simple color-coded indicators typical of most air purifiers on the market. In addition, it allows you to track your real-time and historical air quality measurements in the Blueair app. This air purifier seems like a perfect option for data geeks.
Moreover, the Blueair Classic Pro CP7i offers a good range of purification settings. You can choose between four manually-adjusted fan speeds, an auto mode that adjusts the fan speed based on the air quality measurements, a night mode that operates at the lowest noise levels possible, and an eco mode that conserves energy when pollution levels are low. These settings can be controlled with a touchscreen, or remotely via the app or Alexa voice assistant.
Lastly, there’s HINS Pure. When this feature is enabled, the Blueair Classic Pro CP7i will activate the light sanitizer for 10 seconds every 10 minutes, reducing the germs that got trapped in the filter. It is not obtrusive, though. HINS Pure makes no noise and its bluish light is barely visible through the filter cover at the back.
Blueair Classic Pro CP7i: Performance
- Best suited for rooms measuring 609 square feet or less
- Keeps the air smelling fresh and clean
- Exceptional performance in air quality tests
The Blueair Classic Pro CP7i is recommended for rooms measuring up to 609 square feet (56.5 square meters), which corresponds with its Clean Air Delivery Rates (CADR). These independent ratings indicate how quickly an appliance can clean the air in a given space, and are usually measured in cubic feet per minute (CFM).
This air purifier is rated 380 CFM for pollen, 231 CFM for dust and 393 CFM for smoke. Based on the general rule that the CADR should be at least two-thirds of the room’s square footage, this means the CP7i is capable of cleaning the air in a space measuring 609 square feet four times per hour. That said, it can still be largely suitable for spaces up to 1,400 square feet (130 sq m) as per Blueair’s claims, but the rate will then drop to two air changes per hour.
Complex specs aside, we were more than impressed with the day-to-day performance of our Blueair Classic Pro CP7i. The first thing we noticed was how quiet this air purifier was. Most of the time, we could not even hear it working. When we measured its noise levels with the Sound Meter decibel-counting app, we noted just 52 dB at the highest fan speed — that is equivalent to the sounds made by a refrigerator. For an air purifier this size, this is exceptionally quiet.
The second thing we noticed was the change in the air quality. After just a few days of running the Blueair Classic Pro CP7i, the air in our house became noticeably fresher. Our hay fever symptoms also seemed to subside. While we could not verify the germ-removing properties of this air purifier (we did not have any complex microbial testing kits at hand), the air in our house did seem “easier to breathe” than when we treated it with different air purifiers in the past. But we can’t say for sure whether that was down to the HINS Pure feature.
What we could verify, however, were its particle-removal properties in medium-sized rooms. We performed a series of tests using an industry-grade Perfect Prime air particle counter, a device capable of detecting airborne contaminants as small as 0.3 microns.
We started with an ambient air quality test, where we ran the Blueair Classic Pro CP7i in auto mode for 15 and 30 minutes, and noted the differences in the air quality measurements over time. The results were promising. After 15 minutes, this air purifier removed 69% of particles measuring 0.3 microns and 71% of pollutants measuring 2.5 microns (no 10-micron particles were detected). After half an hour, these values rose to 79% and 88%, respectively. Considering that both the CP7i and air particle counter indicated good air quality at the time of testing, these numbers were quite impressive.
We got even better results during our smoke tests. First, we burned 10 matches, then we ran the Blueair Classic Pro CP7i on its auto setting. After 15 minutes, the purifier removed a staggering 97.6% of 0.3-micron particles, 98.9% of particles measuring 2.5 microns, and all the pollutants larger than 10 microns. After 30 minutes, the air quality had returned to its baseline levels. When we repeated this match test on the highest fan setting, all the pollution was gone after just 15 minutes, and the air quality after 30 minutes was better than before we started the test.
Next, we burned five incense sticks and followed the same testing procedure. On both the auto mode and highest fan settings, the Blueair Classic Pro CP7i hoovered up almost all particles after 15 minutes, with the air quality readings after 30 minutes proving better than at baseline. All in all, this air purifier is a force to be reckoned with, and we can confidently stand behind its performance claims.
Blueair Classic Pro CP7i: User reviews
The Blueair Classic Pro CP7i is rated 4.5 out of 5 at Amazon, with approximately three-quarters of users giving it a full five stars. Positive reviews often praised this air purifier for its good-quality build, detailed air quality measurements and ability to eliminate various household odors.
As one happy buyer said: “This air purifier works! Amidst all of the crazy southern pollen coming into our home you hear the purifier turn on and clean the air. Better yet, people walk in our home and compliment us on how ‘clean’ it smells and ask us what we use to clean our air. We point them straight to this — literally nothing else!”
Negative reviews, on the other hand, tended to mention individual faulty units, with one user also pointing out that Blueair Classic Pro CP7i does not support 5GHz and 6GHz WiFi networks.
Should you buy the Blueair Classic Pro CP7i?
✅ Buy it if: You want a powerful air purifier with germ-busting properties. The Blueair Classic Pro CP7i leaves the air clean and fresh without making excessive noise or ravaging your energy bill. Plus, its robust air quality monitoring is hard to match.
❌ Do not buy it if: Space or money are tight. The Blueair Classic Pro CP7i is a beast of an air purifier, both in terms of its size and its performance, and we would not consider it affordable for most people.
If Blueair Classic Pro CP7i is not for you
We can’t think of a better alternative to the Blueair Classic Pro CP7i than the Molekule Air Pro. This stylish appliance features a patented PhotoElectroChemical Oxidation (PECO) technology that has been shown to destroy bacteria, viruses and other minuscule germs, as well as a cylindrical HEPA filter and some of the best smart features we have ever seen in an air purifier. However, the Molekule Air Pro also costs a whopping $999.99, making it even less budget-friendly than the CP7i.
Not fussed about eliminating germs? Then the Levoit Core 600S should land on your radar. This powerful air purifier takes the top spot in our guide to the best air purifiers on the market, and for a good reason. It is an excellent choice for large rooms, and it costs half the price of the Blueair Classic Pro CP7i.
Looking for something more affordable? Consider the Blueair Blue Pure 411i Max. It is a great budget-friendly pick for small- to medium-sized rooms. This compact air purifier costs only $169, but it delivers exceptional air-cleaning performance and shares plenty of app features with the CP7i.
Blueair Classic Pro CP7i: How we tested
We spent over a month testing the Blueair Classic Pro CP7i, assessing its design, features, day-to-day performance, ease of use and connectivity with third-party devices. We also measured how loud this air purifier was on different settings using the Sound Meter decibel-counting app, and checked the cost of the replacement filters.
Lastly, we performed a series of tests using an industry-grade Perfect Prime air particle counter, a device capable of detecting airborne contaminants as small as 0.3 microns. We started with an ambient air quality test, where we ran the Blueair Classic Pro CP7i on its auto mode for 15 and 30 minutes, and noted the differences in the air quality measurements over time. Next, we conducted several smoke tests to see how this air purifier handles severe pollution. We burned matches and incense sticks, then recorded the changes in air quality readings after running the Blueair Classic Pro CP7i for 15 and 30 minutes on auto mode and highest fan speed.
