Why it matters
The Alen BreatheSmart 45i is a HEPA room unit air purifier that its maker rates for 1,900 sq ft.
At the usual 4.8 air changes an hour and an 8-foot ceiling, a 1,900-square-foot rating implies about 1,216 cubic feet of clean air a minute. In a 12-by-15-foot bedroom that would turn the air over roughly 51 times an hour.
Filtration: HEPA.
Price-wise it sat in the dearest third of the 74 hepa room unit models we cover when we checked; the button shows today's price.
It qualifies for our lists Best Air Purifiers for Large Living Rooms, Best Smart Air Purifiers With App Control, where it is ranked against every model that meets the same rule.
Its rated room size of 1,900 square feet is above the middle of the range we cover: 113 of the 152 purifiers with a stated figure come in lower, and the range runs from 62 square feet to 4,800 square feet.
Compared with the Alen BreatheSmart 25i: rated room size 1,900 sq ft here vs 800 sq ft.
Who it's for, and who should skip it
Good fit if
- Rooms up to about 1,900 sq ft
- Large open rooms
Look elsewhere if
- Whole-home filtration on its own
- Removing gases without a substantial carbon stage
Pros and cons
Pros
- Rated for 1,900 sq ft
Cons
- Filters are an ongoing cost
- Size to the room at 4.8 air changes per hour
Limitations to weigh
- Specifications are the maker's or seller's own figures; check fit against your equipment's model number and the actual size.
Specifications
The bracket shows where each figure comes from.
| Price | $449 | Maker |
|---|---|---|
| Room coverage | 1,900 sq ft | Maker |
| Filter type | HEPA | Maker |
Alternatives worth comparing
More air purifiers we cover
- FreAire HAP605 Air Purifier
- AirDoctor AD4000 $679
- Blueair ComfortPure 3-in-1 T20i Air Purifier $599.99
- Winix C545 Air Purifier
- PuroAir 130i Smart HEPA Air Purifier $129.99
All air purifiers, compared in one table · Every Alen product we cover
Final verdict
A solid choice for rooms up to about 1,900 sq ft. Confirm the model it fits before ordering.
Where to buy
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