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breathesmart 45i purifier review

The Alen BreatheSmart 45i is a unit that shows up a lot when searching for the best air purifier reviews. This is a product by Alen- an American company based in Austin, Texas. This company’s air purifiers are highly regarded for their sturdy construction, incredible designs, and personalized air filters.

In this Alen 45i review, we’ll be looking at its general performance in terms of coverage, reliability, power consumption, and noise emissions. We’ve also analyzed reviews from previous buyers to give you a much clearer idea of what to expect and whether or not this is the perfect air purifier for you.

BreatheSmart 45i Air Purifier is Best For:

  • People with allergies– the true HEPA filter used for this air purifier is engineered purposely for removing pet hair, pet dander, mold, dust, dust mites, and pollen, among other allergens. 
  • Anyone who has asthma and other breathing difficulties– besides being able to change the air in your room 5 times every hour, the Alen 45i has an air quality indicator and auto mode to keep the air quality in check. 
  • Homeowners looking for the best air purifier for large rooms– this device promises to be sufficient for rooms up to 800 sq. ft. 
  • It’s yours if you want a powerful yet quiet air purifier– Alen air purification products receive a lot of praise for keeping their noise level down even when cranked to their highest level. 
  • Those who want a sleek air purifier to match their modern décor– you can get this air purifier in a range of designs and colors to perfectly blend with your walls and floors. 
breathesmart 45i auto pilot

Assembly and set up 

Similar to other Alen air purifiers that we’ve reviewed before, you will receive the Alen Breathesmart 45i with a starter filtration kit plus a manual. The air filter comes already installed, so there’s basically no assembly that is required on your side.

However, your new filter will be covered in a wrapping bag, and you’ll need to remove it first. Air purifier manufacturers do this for the obvious reason of protecting the filter from getting dusty during storage and transit. This air purifier’s filter kit is positioned in a compartment, which is covered by the panel at the front. The panel snaps right off without the need for any tool. 

The Alen 45i does not require any complicated smart control set up. Just plug it in, and it’s ready for the job. 

Quality of Construction and Design 

If there’s one thing that makes Alen one of the best air purifier brands in 2020, then that has to be the level of construction quality that it endows its products with. What the review team at AirHonest appreciates is that Alen uses a combination of thick plastic and metal to give you an air purification device that you’ll probably use for years.

This unbeatable construction is again complemented by a lifetime manufacturer warranty, which is a significant telltale of how confident Alen is with this purifier. If your unit starts malfunctioning, you are assured of either a new or refurbished replacement forever. 

Another area of this device that gets a lot of rave in most Alen Breathesmart 45i reviews is the design aspect. When buying this air purifier, you’ll have 14 undeniably beautiful front panel designs to choose from. From graphite to oak and weathered gray, there’s no doubt that you’ll be able to personalize your air purifier to match your modern décor.

View BreatheSmart 45i On Amazon

What is the size of the Alen Breathesmart 45i? 

The Alen 45i measures 8.5” (L) x 15” (W) by 25” (H) and weighs a little under 15 pounds. At this size, this air purifier is neither bulky nor the most compact. In our opinion, this is just the right size for a large room air purifier that is meant to add to your aesthetics without consuming a lot of space whether you choose to use it in a bedroom, nursery, living room, kitchen, basement, or office.  

Regarding placement, this is a device that you can position just about anywhere. While it’s possible to place it on a desktop, its aesthetics aspect comes out nicely when used on the floor. 

breathesmart 45i living room

How the Alen Breathesmart 45i Cleans your Air

Basically, a motor-powered fan inside this device pulls air through the narrow space left on both the right and left-hand sides of the purifier. Once inside, the air is drawn across the thick air filtration kit, where all the magic happens. The cleaned air is then pushed back into the room through a grill at the back top. 

Now, this particular model that we are reviewing here comes fitted with Alen’s HEPA silver filter. This will be your perfect screen if you want to combat bacteria, mold spores, germs, fungi, viruses, dust, odor, and allergens, such as pet hair and dander. 

If your primary problem is allergies and dust, there’s an option to get this air purifier with Alen’s HEPA Pure filter, which is a little bit cheaper and just perfect for these contaminants. 

Optional Ionization technology 

There is a lot of talk going on regarding ionic air purifiers. Although most experts point out that ionization technology is safe even for people with respiratory-related ailments, such as asthma, some people are still worried about its safety. 

The Alen 45i air purifier employs this purification technology. The best part, however, is that there’s an option to turn it ON/OFF depending on your stand. 

Controls, Modes, and Special Features 

Similar to other Alen air purifiers that we’ve reviewed before, the 45i is controlled via the interface at the top only. It does not have a compatible app or remote control, but this isn’t an issue. 

breathesmart 45i touch panel

The control panel itself is feather-lite sensitive, and all the buttons are nicely spaced and labeled. This interface has pretty much all the key features that make the best air purifiers for homes and offices. You’ll get; 

  • Ionizer on/off function.
  • Filter life indicator light. 
  • 3-timer button (2, 4, and 12 hours).
  • Auto mode with a light ring that cycles between red, orange, green, and blue to show air quality.
  • 4-speed fan settings.
  • Child-lock feature that locks in settings from kids and pets. 



According to the manufacturer, the Alen 45i air purifier is capable of servicing medium to large spaces of up to 800 sq.ft. on the highest fan setting, and 250 sq. ft. on low speed. Alen 45i CADR is 245 and falls within the acceptable range for a medium-to-large house air filter. On the other hand, its ACH (Air Changes per Hour) of 2x to 5x means that it can change the air in your room up to 5 times every hour. 


Going through most Alen Breathesmart 45i air purifier reviews, you might notice that most of the previous buyers report that their devices are incredibly quiet, especially at lower fan-speed settings. That’s because this device is engineered with Alen’s WhisperMax technology, which puts the noise output at between 39 dB and 56 dB. For comparison, the noise level ranges from a whisper in low settings to gentle rainfall.

Is it power efficient?

Well, air purifiers are generally power efficient except a few that also double as a fan (case in point: Dyson air purifiers). The Alen 45i is a low energy consumption device that uses 50w only at the highest speed. Simple calculations show that you’d pay 4.8 cents to run this air purifier for 8 hours daily or $1.4 a month. 

Maintenance and Warranty 

breathesmart 45i filter replacement

As we mentioned earlier on in this Alen 45i review, your purchase will be covered with a lifetime warranty once you get this unit. It also doesn’t require any complicated maintenance.

Besides using a dry cloth to wipe its exteriors whenever it gets dusty, the major maintenance that this unit requires is filter replacement every 9-12 months. The filter replacement light on the control panel will light up when it’s time to do so.

Pros & Cons

Pros 👍
✔ Effective and personalized air filters
✔ Sleek design with customized front panel
✔ Incredibly quiet operations at low fan speed
✔ Has auto mode and child-lock feature
✔ Unbeatable warranty deal

Cons 👎
✘ Relatively on the pricier side
✘ Customized filters come at a price too
✘ A tad heavier

Our Verdict 

We can’t doubt that Alen air purifiers do come at a notably higher price tag. However, we can’t also despise the fact that this manufacturer has done everything to ensure that you are getting exactly what you are paying for.

The Alen 45i air purifier ticks all our boxes of what could be the best air purifier for 2020, including an air quality sensor mode and a child-lock feature to keep curious fingers and paws away. The ability to personalize the front panel design as well as the filter, again, is another versatility that we rarely see in most inexpensive air purifiers on Amazon.

Frequently Asked Questions

Can I place the Alen 45i against a wall?

The air intake of this unit is on the sides while the outlet is at the top. So, it’s safe to position it near a wall.

Is this air purifier ideal for smoke and chemical fumes?

This air purifier’s filter setup isn’t engineered for smoke removal. However, you can customize your air purifier by getting the HEPA Fresh filter that is meant for smoke and fumes.

Does the Alen 45i release ozone into the air?

Besides the filter kit, this air purifier also uses ionization technology to remove contaminants in the air. Ionization does not create ozone, and it’s safe even for people with respiratory-related problems. If anything, there’s an ON/OFF button for the same.