Picking the best air purifier out of an infinite sea of intelligent devices can be a challenge, but looking at name-brand models is a great place to start. Today, we’re going to check out the BreatheSmart 45i by Alen, a proven name that makes some of the world’s best air purifiers. If you’re familiar with the older yet amazing FLEX, then prepare to be blown away by the enhanced purifying power of the 45i.
Purifying Performance
Let’s get straight to the point. Alen’s biggest claim is that each of its BreatheSmart models is designed to cover rooms of any size in any home. With the 45i’s 800-square-foot cleaning range, it seems that this claim holds. This device would work beautifully in any room you might have at home, from single bedrooms to garage workshops and even basement hobby rooms.
The 45i has four different fan speeds that do a complete sweep of a room’s air anywhere between two and five times per hour. The CADR ratings for this device are 208, 194, and 230 for dust, smoke, and pollen respectively. Now, these aren’t the highest figures you’ll see in an 800-square-foot class, but it does more than a decent job in most situations.

Customizable HEPA-Style Filters
One of BreatheSmart’s trademark features is being able to swap out filters depending on your unique situation. The 45i has four different compatible HEPA-style filters: Pure (standard), Fresh (an activated carbon layer that traps odors), Silver (anti-microbial), and OdorCell (destroys odor particles on a molecular level).
One question you might have is why did Alen opt for HEPA-style instead of actual True HEPA Filters? Despite being the only practically guaranteed type that traps every usual airborne particle, it also inhibits airflow. For maximum reach, the 45i uses HEPA-style that still traps more than 99% of particles as small as 0.3 microns.
Optional Ionizer
To have your home smelling its finest, this 3-stage air purifier comes with a fourth optional filter. The ionizer electrically charges airborne particles so they better adhere to the HEPA-style filters. It’s a nice feature to have, especially if you live in a particularly polluted part of the globe.
Just note that no matter what the manufacturer says, ionizers are rarely ozone-free. Ozone is a lung irritant that can lead to harsh breathing problems after prolonged exposure. Use the ionizing feature of the 45i only when nobody’s at home (including your pets).

Auto-Mode with Intelligent Air-Quality Sensors
The biggest headache anyone can have when owning and operating an air purifier is shutting it off when it’s no longer needed. But with an intelligent sensor, such as the one fitted into the 45i, you don’t need to worry about a thing. Just set it and forget it. Simple as that.
On auto-mode, the 45i will select one of its speed presets to efficiently and effectively eliminate airborne particles without going overboard. The sensor is pretty accurate, but it does tend to take a while to shut off. However, it’s better to over-purify the air in a room than under-purify.
55-db Noise Output
More likely than not, if you get an air purifier, it’s going to run continuously throughout the day, and with its intelligent sensor, there’d be no reason to manually shut it off. However, hearing constant droning from the corner of a room can be a pain. It isn’t the case with the BreatheSmart 45i.

This device produces a moderately quiet 55 decibels of noise output on its max speed setting. On sleep mode, you’ll hardly notice that it’s there quietly doing a thorough job. The barely audible noise levels from the 45i make it an ideal air purifier for home offices and dorms.
Customizable Front Panel
Performance-wise, there’s no question that it works flawlessly in small, medium, and large rooms of up to 800 square feet, but what about its looks? After all, it’s going to reside in a room almost indefinitely so it has to look good, right? Don’t worry, it’s got aesthetics in the bag.
You can choose up to seven different front panels to perfectly match any interior design scheme you have going on. Best of all, if you’re tired of one front panel, you can swap it out for another (sold separately). Now that’s customizable!

Single Reviews
Alen BreatheSmart FLEX
Alen BreatheSmart 45i HEPA Air Purifier
Alen BreatheSmart 75i
Alen BreatheSmart FIT50
Alen BreatheSmart Classic
Comparison Articles
Alen vs. RabbitAir vs. Molekule
Verdict: Should I Get the Alen BreatheSmart 45i?
Great airflow and cleaning power? Check. Check. Auto-mode with intelligent sensors? Check. Customizable filters and front panel?
The BreatheSmart 45i from Alen has it all: excellent performance and ultra-convenience to make your living space even more livable. And it has a far 800-square-feet reach to boot. If you’re looking for one of the best air purifiers, your search is over. The Alen BreatheSmart 45i HEPA Air Purifier is definitely for you.
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Last update on 2023-09-26 / Affiliate links / Images from Amazon Product Advertising API
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