Not as effective as higher-priced models
Deeper smart-home integration would be nice to have
Air pollution is a legitimate health hazard. In major cities across Asia, smog generated by rapid industrial growth, crop burning, and pollution has reached a point where aids such as face-masks and air purifiers have become necessary additions to the home. In India, Xiaomi spotted the opportunity early and introduced the Mi Air Purifier 2 in 2016. Several years later, the company is introducing the next generation Mi Air Purifier 3.
Does the new model add enough to justify an upgrade? We find out in the Android Authority Mi Air Purifier 3 review.
Mi Air Purifier 3 review: The big picture
The Mi Air Purifier, when it launched in India back in 2016, made a leap towards making air purification equipment accessible. Similar models from competing brands remain significantly more expensive, and the associated cost of replacement filters is another factor in reducing access. Xiaomi circumvented this through scale.
By making the hardware reasonably priced, far more consumers are able to buy them. This lets Xiaomi make money on the air filters through scale, rather than driving up price points — a classic Xiaomi strategy.
Xiaomi’s M3 carries over the basic design of the Mi Air Purifier 2S. A tall and slim box, the design is minimal, and the matte white finish goes well enough with most decors.
For functional reasons, air purifiers can’t really be hidden. The nondescript design of the Mi Air Purifier 3 becomes all the more important. There are, however, a few distinct changes.
The top grille has been switched from a circular cut-out to a square design. A switch in the internal fan structure accompanies this new grille. We’ll talk more about this shortly.
Elsewhere, physical buttons have been replaced by an upgraded circular OLED panel that is touch-capable. Switching between modes is now accomplished via the touch panel. The display shows the current AQI levels in the room, with a smaller row displaying the ambient temperature, humidity level, as well as the selected mode.
That’s about it for physical changes. The perforated grille running along three of the four sides is the same. So is the easy-to-remove back panel for accessing the filter assembly. I’ve tested a range of air purifiers and I honestly believe Xiaomi has the most accessible and easy-to-use system out there.
How well does the Mi Air Purifier 3 perform?
In a significant change, the Mi Air Purifier 3 finally ships with a true HEPA Class 13 filter instead of the EPA filter that was included with previous models. Interestingly, the Class 13 replacement filters are compatible with Xiaomi’s older air purifiers. This means you should be able to upgrade your older purifier at your next filter replacement cycle.
The Mi Air Purifier 3 finally gets a true HEPA Class 13 filter.
It certainly makes business sense for Xiaomi to convince users to replace their filter on occasion rather than convince them to buy an all-new purifier (just to side-step a filter purchase).
The included HEPA filter is rated to clear out 99.7% of smoke, dust, spores, and fine particles. While it is hard to test just how much this filter improves over the regular EPA filter, my standalone air quality sensor showed the air purifier was certainly doing its job. About 45 minutes into running the air purifier, the ambient air quality however around the 60-70 PM2.5 mark on the air quality index. This isn’t perfect, but in a large unsealed space, it is still a vast improvement over the 250+ levels without the purifier. A quick sniff test also confirms a complete absence of pollution-related smell.
Along with the HEPA filter, the Mi Air Purifier 3 also gains a new centrifugal fan. Xiaomi claims a clean air delivery rate of about 380 cubic meters per hour. This is a significant upgrade from the 310 cubic meters per hour rating of the previous model, and also has an impact on the coverage area.
I tested the Mi Air Purifier 3 using an independent air quality sensor that I placed at the other end of a room of about 405 square feet. With ambient PM 2.5 levels of about 250, I set the Mi Air Purifier to automatic mode. It was able to bring PM 2.5 levels down to under 100 in about 15 minutes. This required the fan to run at full blast, which was fairly noisy. Once the initial air scrub was complete, the fan speed dropped and it took another 15 minutes to bring PM 2.5 levels down to sub 50 levels. The Mi Air Purifier 3 was noticeably more efficient and quicker by almost 10 minutes when compared to a similar test performed on the Mi Air Purifier 2S.
Individual filters are rated to last between three and six months. In my experience, a city like New Delhi, with high air pollution levels, will require you to replace the filter about every four months.
How smart is the Mi Air Purifier 3?
The new purifier includes deep integration with Xiaomi’s Mi Home app, and, to a lesser extent, the Google and Amazon smart ecosystem.
It is a cinch to connect the Mi 3 to the Mi Home app where you can see not only air quality metrics, but also control all the functions and schedules. Connecting to smart speakers requires you to enable the Mi Home skill in the Alexa or Google Home app. Once done, you can ask your smart speaker to switch the air purifier on or off. You can also add routines. I configured my unit to switch off every time I stepped out of the house using a Google Home routine and it reliably triggered every single time.
I like that you can switch between modes using the touch screen on display-enabled devices such as the Nest Hub. Unfortunately, you can’t ask your smart assistant directly for an ambient air quality level readings.
Priced at Rs. 9,999, the Mi Air Purifier 3 is one of the most affordable options on the market. Add to that the reasonable cost of replacement filters, which, at Rs. 2199, are cheaper than alternatives, and you can see that this is one of the best deals around. It is also available via Amazon US for $210.
Compared to my BlueAir or Honeywell air purifiers, the Mi Air Purifier isn’t quite effective; however, at half the cost for the unit itself and significantly cheaper filters, the Mi 3 is a very good and affordable first step towards improving air quality in your home.
Mi Air Purifier 3 review: The Verdict
The Mi Air Purifier 3 is an excellent, albeit iterative, step up in Xiaomi’s family of air purifiers. The design is minimalistic and doesn’t stand out, which is just what you want in your home. The connected features are a handy add-on. The most important bit is efficacy. While the Mi 3 isn’t as efficient as significantly higher-priced models, it does the job well enough to provide a palpable improvement in air quality.
Nobody should have to suffer from the ill-effects of poor air quality. The Mi Air Purifier 3 takes a big step forward in democratizing this space.