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Dyson Purifier Hot+Cool Purifying Heating Fan HP4B Air Purifier Review

Tested using Methodology v1.0.1
Reviewed May 13, 2024 at 01:24 pm
Latest change: Test bench update Oct 31, 2024 at 11:22 am
Dyson Purifier Hot+Cool Purifying Heating Fan HP4B Picture
5.5
Pets
6.2
Bedroom
5.2
Particle Filtration Rate
4.6
Particle Concentration

The Dyson Purifier Hot+Cool Purifying Heating Fan HP4B is a Costco-exclusive variant of the Dyson Purifier Hot+Cool Purifying Heating Fan HP04. It's an all-in-one device that functions as an oscillating cooling fan, space heater, and air purifier. It features Wi-Fi connectivity, so you can remotely operate it with your smartphone via the MyDyson app or with voice commands made using Amazon Alexa, Apple Siri, or Google Home.

Our Verdict

5.5 Pets

The Dyson HP4B is an inadequate option for pet owners. It struggles with trapping really fine particles like cat dander, and its clean air delivery rate is pretty slow. On the upside, you can operate it from far away, and it makes very little noise while running at its lowest fan speed unless you turn the heater on.

Pros
  • Also functions as a cooling fan or space heater.
  • Automatic fan speed adjustment.
Cons
  • Poor particle filtration performance.
  • Low clean air delivery rate.
  • Noisy operation when heater is turned on.
6.2 Bedroom

The Dyson HP4B is a passable choice for bedrooms. It's worth a look if you want something that can act as a fan or space heater, but its actual performance as an air purifier is pretty poor. It's somewhat noisy when running with its heater turned on, which is something to be aware of if you leave it running on colder nights.

Pros
  • Also functions as a cooling fan or space heater.
  • Automatic fan speed adjustment.
  • Night mode dims display.
Cons
  • Poor particle filtration performance.
  • Low clean air delivery rate.
  • Noisy operation when heater is turned on.
5.2 Particle Filtration Rate

Pros
  • Also functions as a cooling fan or space heater.
  • Automatic fan speed adjustment.
Cons
  • Poor particle filtration performance.
  • Low clean air delivery rate.
  • Noisy operation when heater is turned on.
4.6 Particle Concentration

Pros
  • Also functions as a cooling fan or space heater.
  • Automatic fan speed adjustment.
Cons
  • Poor particle filtration performance.
  • Low clean air delivery rate.
  • Noisy operation when heater is turned on.
  • 5.5 Pets
  • 6.2 Bedroom

Performance Usages

  • 5.2 Particle Filtration Rate
  • 4.6 Particle Concentration
  1. Updated Oct 31, 2024: Converted to Test Bench 1.0.1.
  2. Updated May 13, 2024: Review published.

Differences Between Sizes And Variants

The Dyson HP4B is available in only a single colorway: 'White/Silver.' You can see the label for our test unit here.

Let us know in the comments if you come across another variant of this machine.

Compared To Other Air Purifiers

The Dyson HP4B is a combination air purifier, fan, and space heater that's best suited for small to medium-sized rooms. Like most other Dyson HP models, it isn't particularly impressive as an air purifier, with poor particle filtration performance and a low air cleaning rate. However, it does have some value as a cooling fan and space heater. The suite of onboard particle sensors also allows you to keep tabs on your home's air quality, even when you're away from home, thanks to its Wi-Fi connectivity.

Dyson Purifier Hot+Cool HP07

The Dyson Purifier Hot+Cool HP07 is better than the Dyson Purifier Hot+Cool Purifying Heating Fan HP4B, which itself is simply a Costco-exclusive variant of the Dyson Purifier Hot+Cool Purifying Heating Fan HP04. The HP07 simply operates a little more quietly and has a higher clean air delivery rate.

Test Results

perceptual testing image
Design
Design
Body
Height 30.2" (76.8 cm)
Width 9.8" (24.8 cm)
Depth 9.8" (24.8 cm)
Weight
11.8 lbs (5.4 kg)
Power Cord Length 74.2" (188.5 cm)
Wheels
No
Design
Display And Control
Filter Change Indicator
Yes
Air Quality Sensor Auto Mode
Yes
Remote Control
Yes
App
Yes
Display On/Off
Dimmable only
Timer Function
Yes
Number Of Fan Speeds
10

This device's display provides information on ambient particle quantities. You can cycle through a live view of room temperature and humidity, PM2.5 particle concentration, PM10 particle concentration, Volatile Organic Compound (VOC) level, and nitrogen dioxide level. The color of the indicator strip along the side of the display changes based on air quality.

  • Green: Good
  • Yellow: Fair
  • Orange: Poor
  • Red: Bad

This air purifier also comes with a remote control that allows you to change the air purifier's fan speed, adjust the fan's oscillation, cycle through particle count info, change the intensity of its heating element, or enable the device's Night mode, which dims the display, but doesn't shut it off, and sets the fan to its quietest setting. This remote is magnetized and is meant to be placed on top of the oval-shape fan when not in use.

Design
Filter Configuration
Filtration Layers
2 Stage
Activated Carbon
Sheet

This air purifier has a two-stage filter system comprising a HEPA filter and an Activated Carbon layer for locking in odors. However, the actual quantity of carbon isn't likely to be sufficient for locking in most VOCs.

The manufacturer doesn't issue any maintenance requirements for the filter system, but you should replace it every 12 months or whenever the device notifies you. You can buy a replacement here.

Performance
5.2
Performance
Particle Filtration Rate
Air Cleaning Rate
278 m³/Hour
4.6
Performance
Particle Concentration
Average Final 0.3 µm Concentration
266 particles/L
6.7
Performance
Noise
Noise @ Lowest Fan Speed
34.2dBA
Noise @ Highest Fan Speed
55.1dBA

Turning on the Dyson's heater and leaving it in its highest setting results in an increase in operating noise at lower fan speeds:

  • Noise @ Lowest Fan Speed: 42.2dBA
  • Noise @ Highest Fan Speed: 55.1dBA