Alen BreatheSmart 75i
#12 in Large roomsFull review
A premium large-room purifier with long-lasting filters, for buyers willing to pay for quiet and a subscription-backed guarantee.
Amazon $699.59$699.59
2.7/5
A large-room purifier with strong certified CADR and odor filtration, but high filter costs.
- 370 cfmSmoke CADR
- 574 sq ftRoom size
- $239.90/yearFilters
Check price at Amazon$679
Price checked October 22, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Certified 370 CFM for large rooms
- Combined carbon and HEPA filter in one unit is simple to change
- PM2.5 sensor and auto mode
Cons
- Filters cost about $240 a year
- Expensive at about $680
- Long warranty requires a filter subscription
- No published noise figures
How it scores
The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its room size. How we rank explains each one.
Specifications
| Model number | AD4000 |
|---|---|
| Performance | |
| Smoke CADR | 370 cfm |
| Dust CADR | 393 cfm |
| Pollen CADR | 450 cfm |
| PM2.5 CADR | 381 cfm |
| CADR certified by | ENERGY STAR |
| Room size (AHAM) | 574 sq ft |
| Coverage (maker) | 2,776 sq ft |
| Efficiency | |
| Efficiency (IEF) | 5.6 cfm/W |
| ENERGY STAR | Yes |
| Energy use | 396.2 kWh/year |
| Filters | |
| Filter | UltraHEPA with carbon/VOC filter and pre-filter (single filter unit) |
| Activated carbon | Yes |
| Replacement | AD4000 filter unit |
| Replacement cost | $119.95 every 6 months |
| Yearly filter cost | $239.90/year |
| CARB certified (ozone) | Yes |
| Controls and build | |
| Air-quality sensor | PM2.5 |
| Auto mode | Yes |
| Fan speeds | 6 |
| Weight | 15.8 lb |
Alternatives in this room size
Levoit EverestAir
#13 in Large roomsFull review
A premium Levoit for a large room where floor space is tight. The Core 600S cleans a bit more air for less money if you have the floor space.
Amazon $499.99$499.99
Medify MA-112
#14 in Large roomsFull review
A very high-CADR purifier for large open spaces, with high filter costs to match.
Amazon $594.99$594.99
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