Why it matters
The Alen BreatheSmart 35i is a HEPA room unit air purifier that its maker rates for 1,400 sq ft.
At the usual 4.8 air changes an hour and an 8-foot ceiling, a 1,400-square-foot rating implies about 896 cubic feet of clean air a minute. In a 12-by-15-foot bedroom that would turn the air over roughly 37 times an hour.
Filtration: HEPA.
Price-wise it sat in the middle 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 Basements and Musty Odors, Best Smart Air Purifiers With App Control, where it is ranked against every model that meets the same rule.
Its rated room size of 1,400 square feet is above the middle of the range we cover: 93 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 75i: rated room size 1,400 sq ft here vs 2,800 sq ft; replacement interval every 6-9 months here vs every 10-12 months.
Who it's for, and who should skip it
Good fit if
- Rooms up to about 1,400 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 1,400 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 | $289 | Maker |
|---|---|---|
| Room coverage | 1,400 sq ft | Maker |
| Filter type | HEPA | Maker |
| Replacement interval | every 6-9 months | Maker |
Alternatives worth comparing
More air purifiers we cover
- GermGuardian AC4825E HEPA Air Purifier Tower
- Hathaspace HSP002 Air Purifier
- Airpura C600/C600DLX Air Purifier (C600-BLK) $1,049.98
- Honeywell HPA020 Air Purifier
- Honeywell PowerPlus HPA3100 Air Purifier
All air purifiers, compared in one table · Every Alen product we cover
Final verdict
A sensible choice for rooms up to about 1,400 sq ft. Confirm the model it fits before ordering.
Where to buy
Each button opens this exact model. We may earn a commission on tracked links; it never changes what we publish. Disclosure