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alen breathesmart flex product 1 2

Alen air purifiers are known for their elegant design, high level of customization, and relative affordability. These units also receive a good press for their wide coverage. The purifier that we review here, the Breathesmart Flex, for instance, claims to pack enough oomph to cover up to 700 sq.ft.

This makes it an attractive choice for homeowners who want a powerful air purifier for large spaces, but don’t want to spend so much on one. So, let’s see how it stacks up to the competition, and whether or not it’s a good buy.

Check BreatheSmart Flex Air Purifier on Amazon (Link Opens in a New Tab)

Alen BreatheSmart Flex is Best For:

  • Those with large sitting rooms or bedrooms– this air purifier offers a coverage of up to 700 sq.ft.
  • Those with allergies and asthma– the Flex uses a HEPA (High-Efficiency Particulate Air) filter that has been proven to remove most household air pollutants that may worsen respiratory problems. These include dust, pet dander, dust mites, and mold spores.
  • Pet owners with fur shedding issues– this purifier also traps dog and cat fur in the air.
  • If you value style– this model offers 14 customizable panels with modern wood trim designs to adorn your décor.

Assembly and Set up

The Flex comes virtually fully assembled and ready to use right out of the box. However, you’ll need to unwrap the plastic packaging on the air filter first. Next, reinstall the filter and plug the power cord into the socket. That’s all.

Construction Materials and Design Review

The Alen Flex is a full-size air purifier mainly made of metal. We’ve come across air purification units with very high price tags despite their flimsy plastic construction. So, this model’s metallic build is an excellent value, especially at its mid-range price tag.

The front panel is available in different colors and styles. Even better, it is interchangeable. This offers you the flexibility to match the style of this air purifier to your current home décor.

The control interface is a touch-sensitive 4.5-inch wide panel at the top. What we like about it is that the 5 buttons have been nicely spaced and labeled for easy use.

breathesmart flex bedroom

Size and Placement Review

This unit measures 15 (length) by 8.5 (depth) by 25 inches (height). While it’s not the smallest air purifier out there, it does not seem to clutter most small-to-large spaces that we’ve seen it placed.

breathesmart flex dimensions

It has quite some heft to it, though, at 15 lbs. Fortunately, there is a sturdy handle at the back. So, moving it from the living room to the bedroom won’t be so difficult.

The Breathesmart Flex is a floor air purifier. Considering its height, though, you’ll have no issues placing it on a slightly elevated top. The latter idea makes more sense if you are a smoker or live with one.

The ideal spot to position an air purifier is at the center of the room- but this is usually not applicable in most typical household settings. This leaves you with 2 more options; along the wall and towards the corner.

Wherever you decide to position it, be sure to leave a clearance of about 15 inches from any obstacles. This will help maintain an unobstructed airflow in and out of the purifier.

How does the BreatheSmart Flex Work?

Similar to most modern air purifiers, the Flex starts by sucking air through a vent at the bottom. Here, the air goes through a preliminary screen that filters some of the large air contaminants before reaching the HEPA filter. This pre-filter is removable and washable and practically prolongs the lifespan of the HEPA.

From the pre-screen, the air is then passed through a HEPA filter (more about it below) where most common household contaminants are trapped. Purified air later comes out from a grill at the top. 

What air pollutants does it remove?

This is a critical question when buying most Alen air purifiers. The reason for this is that unlike other manufacturers that use 1 type of air filter for their units, Alen offers a choice of 4.

Worth noting, each of these filters has a different filtration capability depending on the air contaminants in question. This allows you to customize your air purifier with the perfect filter that tackles the pollutants that are disturbing you.

Another thing worth mentioning here is that while Alen’s purifiers are HEPA, they are not certified as True HEPA.

The name HEPA (High-Efficiency Particulate Air) is used on filters that are capable of removing 99% of air pollutants 0.2 microns or larger. To be certified as True HEPA, the filter should be able to remove 99.97% of air contaminants down to 0.3 microns.

Alen explains that while True HEPA is marvelous, it does restrict airflow, which consequently affects space coverage.

Alen’s 4 Air Filters

  • HEPA-Pure– this is what the Flex purifier comes with. It is an electrostatically-charged filter that captures dust, mold spores, pet dander, and dust mites. It’s not best suited for cigarette smoke and strong smells. It can be replaced with filter model number BF35.
  • HEPA-Fresh– this is a 3-stage filter consisting of a pre-screen, HEPA filter, and Activated Carbon. It captures dust and dust mites, mold spores, and pet dander, among other pollutants. This filter also removes light smoke and cooking smells. It can be replaced with the Alen A375 replacement filter.
  • HEPA-Silver– this is a 3-stage filter that removes VOCs and other household contaminants including dust, dust mites, pet dander, and mold spores. Its replacement kit is the BF-silver-carbon.
  • HEPA-OdorCell– this filter kit is currently the priciest from Alen. In addition to removing pet dander, dust, dust mites, and mold spores, this filter is a strong odor remover too.

Controls and Modes

The 5 control buttons on this air purifier are the only way of controlling it. It neither comes with remote control nor does it support App connectivity.

This panel has everything you need, though, including a 4-speed motor control button and a timer. A unique function that we don’t see on most air purifiers here is the lock button. This locks your settings so kids won’t be able to change them as they fiddle with the interface.

This model also has a Laser Smart Sensor that detects the air quality in the room. The results are displayed in 3 different colors by a LED Air Quality Indicator around the power button. Unfortunately, the Flex does not have an Auto Mode. So, you’ll need to make the appropriate adjustments in speed fan manually.

alen breathesmart flex top



Alen says that this air purifier can comfortably handle large rooms up to 700 sq.ft. in size. Going by its CADR (245 cfm) and ACH (5x) ratings, this unit will take slightly over an hour to effectively clean the air in such a big room- assuming that it has a ceiling height of 8 ft. This isn’t so bad, in our opinion.

CADR (Clean Air Delivery Rate) shows how fast an air purifier will clean a given room.

ACH (Air Changes per Hour) refers to how many times an air purifier will exchange the air in the room per hour.

breathesmart flex circulation


This air purifier’s noise level is 39 dB at speed 1, 42 dB at speed 2, 49 dB at speed 43, and 55 dB at the highest setting (4). The first 3 settings that you’ll be using mainly make it a perfect choice for most bedrooms. Even at its highest speed level, the Flex is much quieter than a normal conversation which is rated at 60 dB.

How efficient is it?

Despite its broad coverage, it’s quite intriguing that this unit only consumes 56 watts of electricity at the highest speed. If you run it for 12 hours every day at this speed, you’ll be paying 8 cents a day. This equates to around $30 annually, assuming that you pay 12 cents per kilowatt-hour of electricity.

flex white panel removal 2


Maintaining this purifier requires replacing the air filters when necessary. The control panel has a filter indicator that uses 3 colors to alert you on the condition of the screen: green, yellow, and red. Yellow shows that the filter is almost worn out. This is the right time to order a new one. Red will illuminate when it’s time for a replacement.

Alen says that any of its 4 choices of filter will take you 6-12 months depending on usage. Here are the replacements for the filters;

  • HEPA-Pure- BF35 ($)
  • HEPA-Fresh- A375 ($)
  • HEPA-Silver- BF-silver-carbon ($$)
  • HEPA-OdorCell- HEPA OdorCell ($$$)

The pre-filter also needs to be cleaned to increase its effectiveness. This layer is attached with Velcro and can be removed for vacuuming or washing.

Warranty – Perhaps the best part about this air purifier is its lifetime warranty. Whenever your purifier develops issues, you are assured of a similar manufacturer-refurbished purifier with free shipping. Who beats that?

Alen BreatheSmart Flex Pros & Cons

Pros 👍
✔ Compact design
✔ Wide coverage
✔ Quiet operations
✔ Kids and pets friendly
✔ Unbeatable lifetime warranty

Cons 👎
✘ Does not have Auto Mode
✘ Filter replacements can be pricey
✘ Does not use True HEPA
✘ Has no remote or App control

Review Verdict

The Alen BreatheSmart Flex may not be perfect, especially if you consider its filters. However, it makes up for this in a whole lot of ways including a very wide space coverage and a replaceable panel with modern yet classic designs. The greatest of all, though, is the promise of a lifetime warranty.

Frequently Asked Questions

Does the Breathesmart Flex use an ionizer?

No. This model does not use an ionizer. As such, it does not create ozone.

How many air filtration stages does it use?

This will depend on the exact air filter that you choose to go with. This air purifier comes bundled with the HEPA-Pure that features a pre-screen and HEPA filter only. Other optional filters (HEPA-Fresh, HEPA-Silver, and HEPA-Odorcell all feature a 3-stage system).

How soon should I replace the filters?

Alen advises replacing the filters after 6-12 months depending on usage. A filter indicator light will light yellow to alert you when the filter’s lifespan is almost ending, and red when it wears out completely.

Expert Use Tips

  • We suggest vacuuming the pre-filter after every month or 2 to increase its effectiveness.
  • Consider closing the windows when using the purifier to prevent more contaminants from entering.  
  • Leave a clearance of 15 inches all around for increased effectiveness.
  • Place it closer to the source of contaminants to boost efficiency.
  • As much as possible, always plug it directly into a wall socket.

View BreatheSmart Flex Purifier on Amazon