If you want better noise level
Choose Dyson Purifier Big+Quiet Formaldehyde BP04. It scores 4.8 vs 4.0 for noise level, with a 4.1 overall score.
Dyson Purifier Hot+Cool Formaldehyde, HP09 Air Purifier Review
Bottom Line
Choose the Dyson HP09 for premium design, heating, smart air data, and broad purification. Skip it if you need budget value, true air conditioning, or maximum clean-air output per dollar.
Best for
Best for buyers who want one premium device for heating, fan airflow, purification, formaldehyde monitoring, detailed app data, and allergy or odor management. It fits people who value design and year-round versatility as much as raw purifier output.
Not for
Not for shoppers who mainly need a low-cost purifier, true room air conditioning, or the highest CADR per dollar. It is also a poor fit if heat control through the app is essential.
Verdict
The Dyson Purifier Hot+Cool Formaldehyde HP09 earns its strongest praise as a polished all-in-one appliance: reviewers repeatedly liked its design, heating, app data, smoke and odor response, formaldehyde focus, and allergy-related comfort. It is less convincing as a pure value play. Several tests and customers found cooling expectations misleading, high-speed noise noticeable, replacement filters pricey, and clean-air output weaker than less expensive dedicated purifiers. The evidence supports it best for people who will use the heater, fan, purifier, sensors, app, and formaldehyde feature together, not shoppers seeking the cheapest or fastest standalone purifier.
Feature Scorecards
Summary
54 reviewed features-
Very positive 4.5-5.020 (37%)
-
Positive 3.5-4.423 (43%)
-
Neutral 2.5-3.45 (9%)
-
Negative 1.5-2.42 (4%)
-
Very negative below 1.54 (7%)
Pros
-
Design was one of the strongest positives, with frequent praise for the sleek, stylish, premium look.
-
Overall sentiment ranged from enthusiastic recommendations to a few strong customer rejections, producing a mixed but generally positive pattern.
-
Real-time monitoring was a major strength, with detailed app graphs, pollutant data, and visible sensor reactions.
-
Heating performance was frequently praised as fast, warm, and useful, though some users disliked energy use or heat-control limits.
-
Reviewers with allergies or hay fever often reported less sneezing, better symptoms, or better sleep with the purifier running.
-
The app was repeatedly described as easy, useful, and reliable, though one customer reported offline connection failures.
Cons
-
Reliability evidence was negative in customer reports of units stopping after weeks or months.
-
Power evidence was negative in customer/video comments about power use, especially when used for heating.
-
Smart features were useful overall but scored down by customers who could not control heating through the app.
-
One customer reported poor arrival condition with parts and packaging scattered in the box.
-
Durability evidence was negative from a customer whose unit broke in under a year.
-
One customer used it around mold-related basement air and felt the product failed to respond or improve conditions.
Compared With Category Average
Compared with other Air Purifiers, this product is above average in customer support, Wi-Fi reliability, app connectivity, near average in air purification performance, overall satisfaction, below average in mold spore reduction, power consumption, durability.
Comparison summary
53 compared features-
Above average 0.4+ pts higher21 (40%)
-
Same as average within 0.3 pts21 (40%)
-
Below average 0.4+ pts lower11 (21%)
Largest category differences
| Attribute | This product | Category average | Difference |
|---|---|---|---|
| mold spore reduction | 1.0 | 4.1 | -3.1 |
| power consumption | 1.5 | 3.9 | -2.4 |
| durability | 1.0 | 3.3 | -2.3 |
| reliability | 1.0 | 3.0 | -2.0 |
| customer support | 5.0 | 3.0 | +2.0 |
| condition on arrival | 1.0 | 2.8 | -1.8 |
| Wi-Fi reliability | 5.0 | 3.2 | +1.8 |
| smart features | 1.8 | 3.4 | -1.6 |
Consider This Instead
If you want better smart features
Choose Dyson Purifier Big+Quiet Formaldehyde BP03. It scores 4.8 vs 1.8 for smart features, with a 4.2 overall score.
If you want better mold spore reduction
Choose Levoit Core 600S. It scores 4.8 vs 1.0 for mold spore reduction, with a 4.3 overall score.
If you want better durability
Choose Levoit EverestAir. It scores 4.7 vs 1.0 for durability, with a 4.5 overall score.
Compared in Reviews
Products reviewers directly compared with this model, grouped into quick takeaways.
- Better: maximum noise The HP09 was louder at maximum speed than the Dyson Big+Quiet Formaldehyde BP03.
- Alternative: price and missing heat/formaldehyde features PCMag says the TP07 is cheaper if heating and formaldehyde filtering are unnecessary.
AEG AX91-604GY Connected Air Purifier
- Better: cooking-fume clearing speed Ideal Home says the AEG cleared cooking fumes faster than the Dyson in its test.
FAQ
Does the Dyson HP09 purify air well?
Most evidence says yes for smoke, odors, dust events, allergens, and general air-quality cleanup, but some tests found slower or weaker particle reduction than cheaper dedicated purifiers.
Does it actually cool a room?
It works as a fan and can feel cooling when airflow reaches you, but several reviewers stressed it is not an air conditioner and will not truly lower room temperature like one.
Is the heating function good?
Heating is one of the better-supported strengths. Many reviewers said it warmed rooms quickly, though one video reviewer disliked the power draw when using it as a heater.
Is the app useful?
Yes. Reviewers repeatedly praised the MyDyson app for setup, controls, air-quality graphs, pollutant details, and remote monitoring, though heat controls are restricted by safety rules.
Is it quiet enough for bedrooms?
Usually at low or night settings. Many reviewers found it quiet or sleep-friendly, but high fan speeds were often described as loud or noticeably noisy.
Are replacement filters expensive?
They are a recurring cost concern. Some reviewers considered the annual cost reasonable, while others called replacement filters expensive compared with mid-priced purifiers.
Who should pay extra for the formaldehyde model?
The strongest case is for homes with new furniture, renovations, smoke, gas cooking, or concern about formaldehyde and VOCs. If you do not need that feature, some reviews suggest cheaper Dyson or non-Dyson alternatives.
Sample Expert Reviews We Analyzed
These are a few of the reviews included in our analysis.
Video Reviews
YouTube - Watch Before You Buy! - TopFindsReviews
- Review score
- 4.9
YouTube - Sam's Tech Talk
- Review score
- 4.3
YouTube - TotallydubbedHD
- Review score
- 4.2
Article Reviews
womanandhome.com
- Review score
- 4.7
idealhome.co.uk
- Review score
- 4.0
medgrade.org
- Review score
- 3.7
techadvisor.com
- Review score
- 4.6
Top Air Purifiers to Consider
Choose the H7124 if you want a quiet smart purifier for odors, dust, pets, and app control. Skip it if you need foolproof Wi-Fi, wall-facing intake, UV light, or strong...
Pros: particle removal effectiveness, pollen removal
Cons: UV-C light effectiveness, air dryness
Best for quiet, simple cleaning in bedrooms or apartments. Skip it if you need verified large-room CADR value, app control, or guaranteed neighbor-smoke removal.
Pros: particle removal effectiveness, dust removal
Cons: CADR rating, air changes per hour
Best for strong room cleaning, allergy relief, odor control, and simple operation. Skip it if high filter costs, a larger footprint, or possible nighttime fan noise would bother you.
Pros: particle removal effectiveness, HEPA filtration
Cons: customer support, warranty coverage
Choose this if you want strong odor, dust, smoke, and pet-air cleanup with washable filters. Skip it if turbo noise, Wi-Fi setup, or a high upfront price will bother you.
Pros: filter replacement cost, allergen reduction
Cons: Wi-Fi reliability