Short answer
Choose the Dyson Purifier Hot+Cool HP1 if you want the smaller, lighter tower with an H13-classed filter, and you’ll use its heater to top up a well-insulated room. Choose the Philips 3-in-1 AMF870 if you want the figures in writing: a stated CADR, a 2,200 W heater, a yearly filter and quoted noise levels. Either is worth it only if you’ll use all three jobs. For clean air alone, a plain purifier such as Philips’ AC2220 costs much less and states a higher CADR than the Philips tower.
Both towers do three jobs: they filter the air all year, cool you in summer and heat the room in winter, so one machine can stand in for a purifier, a fan and a fan heater. Where they differ most is in what their makers tell you. Philips publishes a CADR, the heater’s wattage, the filter’s life and noise figures for the AMF870. For the Dyson HP1, the UK pages we could read give none of the four. Both are in our comparison of purifier fans and heaters.
Cleaning power (CADR)
Not published; Dyson uses its own room test
270 m³/h for smoke (GB/T 18801-2015)
Heater
Set temperature; wattage not published
2,200 W with a set temperature
Filter Tie
H13 HEPA and carbon; life not published
No class stated; about 12 months
Sensors and app
PM2.5, PM10, temperature; MyDyson app
Adds gas and humidity sensing; Air+ app
Noise
No figure published
19 dB low, 46 dB top, at 1.5 m
Size and weight
76.5 cm tall, 5.3 kg
106.4 cm tall, 8.5 kg
Choose the Dyson Purifier Hot+Cool HP1 (HP11) if you want the smaller tower and an H13 filter, and heat only a snug room.
Choose the Philips Air Performer 8000 Series 3-in-1 Purifier, Fan and Heater (AMF870/35) if you want a stated CADR, a stated heater wattage and a yearly filter.
Cleaning power and CADR
CADR (clean air delivery rate) is the usual way to compare purifiers: how fast a machine lowers particle levels in a test room, in cubic metres of clean air an hour. Philips states 270 m³/h for the AMF870, measured with cigarette smoke to GB/T 18801-2015; on our rule of CADR ÷ 12 that suits a room of about 23 m². Dyson publishes no CADR for the HP1. UK listings base its whole-room claim on Dyson’s own test in an 81 m³ room: a room volume, not a cleaning rate, so it can’t be set against other purifiers, and our tables show it as not published. Even a stated CADR is a lab figure; the UK’s SAGE-EMG paper notes real rooms usually do less well. The Philips wins, because its figure can be compared.
Heater
Both heat to a temperature you set: the Dyson pauses heating once the room reaches it, and the Philips stops too. Philips states the AMF870’s heater at 2,200 W, so an hour at full heat uses about 2.2 kWh. We couldn’t find the HP1’s heater wattage on any UK page we read, and Dyson’s UK description says its heater suits only well-insulated spaces or occasional use, so treat it as a top-up. Philips’ manual sets clear rules for its heater: curtains and bedding at least 1 m from the outlet, a wall socket rather than an extension lead or timer plug, and no bathrooms or kitchens. It adds that the AMF870 doesn’t remove carbon monoxide and is no safeguard against combustion accidents. The Philips wins on what it tells you.
Filter
The HP1 uses one combined filter, Dyson’s 360° Combi Glass HEPA+Carbon, part 965432-01, which Dyson’s copy describes as HEPA H13 with activated carbon. The same part fits many other Dyson purifiers, from the TP04 and HP04 to the TP09 and HP09, so it is widely stocked. It isn’t washable. Dyson’s replacement interval wasn’t on any page we read, but the screen and the MyDyson app show the filter life left. Philips’ FYM860/30 combines a pre-filter, a HEPA layer and activated carbon, and lasts about 12 months by Philips’ estimate, but Philips gives the HEPA layer no class. Neither tower has an ioniser: both manuals list their controls and filter stages without one. A tie: the Dyson states the class, the Philips the interval.
Sensors and app
Both run an auto mode from their sensors and connect to an app. The Dyson reads PM2.5, PM10 and temperature, and shows them on its screen and in the MyDyson app with the filter life and Wi-Fi status. Its continuous monitoring is off by default: hold the remote’s Auto mode button for five seconds to turn it on. The Philips reads PM2.5, gases, allergens, temperature and humidity, and pairs with Philips’ Air+ app. The Philips wins, because it senses gases and humidity as well as particles.
Noise
Philips quotes 19 dB on the AMF870’s lowest setting and 46 dB at the top; its figures are sound pressure measured 1.5 m away. In sleep mode the fan runs slowly and the screen goes dark after three seconds. Dyson publishes no noise figure for the HP1 in the material we could read. The HP1’s Night mode keeps it on its quietest settings with a dimmed screen. For context, a comparison cited in the SAGE-EMG paper measured six HEPA purifiers at 27 to 35 dBA on their lowest flow. The Philips wins, because it gives a figure you can weigh.
Size and weight
The Dyson is the easier tower to fit in and move about: 76.5 cm tall and 5.3 kg, against 106.4 cm and 8.5 kg for the Philips. Dyson’s manual says to lift it by the base, never by the loop on top. The Philips needs more planning. When it heats, it needs a metre between its outlet and any curtains or bedding, a dry, level floor and a wall socket, since an extension lead is out, though not directly below the socket. Both oscillate up to 350° and come with a remote. The Dyson wins.
Is a Dyson worth it, or a plain purifier and a heater?
A 3-in-1 earns its price only if you’ll use all three jobs in the same room. The Dyson and the Philips sit close together on price; the boxes above show today’s figures. If clean air is the main aim, our best overall pick, the Philips AC2220, costs much less than either tower. It states a higher CADR than the AMF870, 420 m³/h against 270 m³/h, though the two figures come from different editions of Philips’ test standard, so treat the gap as rough. Philips also rates its filter for about three years, against about a year for the 3-in-1’s.
Pair a purifier like that with a fan heater you already own, or one you buy separately, and each can stand where it works best: the purifier in the bedroom all year, the heater wherever you need warmth. The heat costs the same either way: a heater’s electricity use is its wattage times the hours it runs, so 2,200 W for an hour is about 2.2 kWh whether it sits inside a 3-in-1 tower or a plain box. Follow that heater’s own safety instructions. The trade-offs are two plugs, two things to find floor space for and, unless you add a desk or tower fan, no cooling breeze in summer.
The tower makes most sense where floor space is short and one room needs warmth in winter, a breeze in summer and filtering all year. Our best air purifiers in the UK covers the plain options, and what an air purifier costs to run sets out power and filter figures for every model we track.
The verdict
On what we could check, the Philips AMF870 is the easier one to judge: it publishes a CADR, its heater wattage, a filter interval and noise figures, and its sensors also cover gases and humidity. The Dyson HP1 is shorter and lighter and names an H13 filter, but you take its cleaning power and heater output on trust. The Dyson is easier to find: we track it at John Lewis, Hughes and Marks Electrical, the Philips only at Philips’ own store. Both carry a two-year guarantee.
Choose the Dyson HP1 if…
- You want the shorter, lighter tower that’s easy to move between rooms
- An H13-classed filter that fits many Dyson models matters to you
- You only need the heater to top up a well-insulated room
Choose the Philips AMF870 if…
- You want a stated CADR, heater wattage, filter interval and noise figures
- You want gas and humidity sensing as well as particles
- You have floor space near a wall socket, a metre from curtains
Neither quite right? For Dyson’s design without the heater, see the Dyson Purifier Cool PC1, or compare every purifier fan and heater we track. If you only need cleaner air, compare every air purifier we track.
How we compared them
- Read Philips’ UK manual, product page and filter page for the AMF870, and Dyson’s HP1 manual.
- Dyson’s own website refused our reader, so the HP1’s other facts come from UK retailer listings that carry Dyson’s product copy.
- Compared the published figures side by side, marking anything a maker doesn’t publish.
- Checked prices at the retailers we track, and show the date we checked.
What we don’t do: lab-test purifiers or measure their noise or heat output ourselves. We found no owner reviews of either tower that we could use.
Dyson vs Philips 3-in-1 questions
Is a Dyson air purifier worth it?
Only if you’ll use what you pay for. The Hot+Cool HP1 makes sense as one compact tower that purifies, cools and tops up the heat in a well-insulated room. If you mainly want cleaner air, a plain purifier costs much less, and Dyson publishes no CADR, so you can’t compare its cleaning with other purifiers. The Philips 3-in-1 does the same three jobs and publishes its figures.
Does the Dyson Hot+Cool have a CADR?
No. Dyson publishes no clean air delivery rate for the HP1. UK listings base its whole-room claim on Dyson’s own test in an 81 m³ room, which gives a room volume but not a cleaning rate, so our tables show its CADR as not published. The Philips AMF870 states 270 m³/h for cigarette smoke, tested to GB/T 18801-2015.
Can I use either one as my main heater?
Dyson’s UK description says the HP1’s heater suits only well-insulated spaces or occasional use, so treat it as a top-up. Philips states 2,200 W for the AMF870, about 2.2 kWh for each hour at full heat, and sets rules for it: a wall socket with no extension lead or timer plug, a metre clear of curtains and bedding, and no bathrooms or kitchens.
Which filters do they take, and how often?
The Dyson HP1 takes the 360° Combi Glass HEPA+Carbon filter, part 965432-01, which also fits many other Dyson purifiers. We couldn’t find Dyson’s interval, so go by the filter-life reading on its screen or in the app; reset it after a change by holding Night mode on the remote. The Philips AMF870 takes the FYM860/30, which Philips expects to last about 12 months. See our guide to replacement filters.
Why has my Philips 3-in-1 stopped heating?
Check three things first. The room may have reached the temperature you set, the filter’s packaging may still be on, or the air inlet or outlet may be blocked: each stops the heater. If the screen shows E6, that is a heater fault, and E1 a motor fault; for either, contact Philips Consumer Care.
