
Alen BreatheSmart 75i Large Room Air Purifier
Air purifiers
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Air purifiers

Air purifiers
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Your starting point
We compare the published specifications relevant to your priority. Each rankable specification counts once; your selected requirements can rule a product out. This is a guide to the numbers, not a laboratory performance score.
Coverage area: 1,400 sq ft vs 500 sq ft room size with 350° oscillation
It is also $50 cheaper.
The trade-off to know
Check first: the Alen BreatheSmart 75i Large Room Air Purifier weighs over 25 lb (11 kg). Tick them under deal-breakers if that rules it out.
Look at the differences ↓Side by side
Start with the key specs, then explore as much as you need.
| What you’re comparing | Alen BreatheSmart 75i Large Room Air Purifier | Dyson Purifier Hot+Cool Formaldehyde HP09 |
|---|---|---|
| CADRPerformance | 350 CFM across Smoke, Dust, Pollen | 190 CFM class (Air Multiplier 77 gallons/sec circulation) |
| Room sizePerformance | Large master suites, open living rooms, offices | Medium to large bedrooms, living rooms up to 500 sq ft |
| Coverage areaPerformance | 1,400 sq ft (2 air changes/hr) / 700 sq ft (4 air changes/hr) | 500 sq ft room size with 350° oscillation |
| Filter typesFilters | Medical-grade H13 True HEPA + Antimicrobial layer + Heavy Odor Carbon | 360° Glass HEPA H13 + Activated Carbon + Cryptomic Formaldehyde filter |
| Filter lifeFilters | 12–15 months extra long filter life | 12 months (HEPA/Carbon) / Permanent Formaldehyde catalyst |
Showing 5 of 11 specifications. Missing values stay unlisted. About the sources
Both sides of the decision
Beyond the spec sheet
Explore the ownership details available for this pair.
Alen BreatheSmart 75i Large Room Air Purifier
Dyson Purifier Hot+Cool Formaldehyde HP09
Physical clearance required for airflow, wall placement, and bedroom noise levels.
Wall Clearance Required
Requires 12 in perimeter airflow space
Cylindrical base: needs 12 in airflow clearance around unit
Nighttime Sleep Mode Noise
Standard sleep speed
28 dB night mode with dimmed LCD
Unit Footprint & Dimensions
Standard room purifier footprint
Bladeless oval loop (30.0 × 8.1 × 8.1 in; 12.6 lb; heats & cools)
Documented ergonomic quirks, hardware annoyances, and maintenance realities reported by real owners.
Alen: What to watch for
Requires periodic filter replacements to maintain airflow and odor capture.
Dyson: What to watch for
High replacement filter cost (~$80 each).
Know what’s behind the comparison
Clinchmark compares manufacturer specifications and other published information. We have not independently lab-tested these products. Editorial assessments and unknown values are identified in the specification details.
Catalog snapshot: September 1, 2026. Prices, availability, and provider terms can change.
Alen BreatheSmart 75i Large Room Air Purifier costs $50 less at list price.
Dyson Purifier Hot+Cool Formaldehyde HP09 has this deal-breaker: over 55 dB on high. Louder than normal conversation at full speed.
Tied on bedrooms. Alen BreatheSmart 75i Large Room Air Purifier is cheaper. The 2 rankable bedrooms specs split 1 to 1. Saves $50 at list price.
Of the 11 specs tracked here, 6 are descriptive and cannot be ranked on numbers alone. Spec sheets also cannot measure subjective factors like build quality, real-world performance, or comfort.