The Honeywell HF09 is our best choice for small rooms: a compact, quiet 5,000 BTU unit that does one job — cooling a small space — and does it well. Here's who it's for, and where it stops.
Honeywell is a trusted name in cooling, and the HF09 is its sensible small-room unit. Rather than chase big BTU figures, it's deliberately built for the spaces where most people actually struggle: a small bedroom, a home office, a study. Within that brief it's excellent — compact, easy to move and the quietest unit we tested. It's our best pick for small rooms in this comparison.
| Model | Price | Cooling power | Suitable for rooms up to | Functions | Rating | Link | |
|---|---|---|---|---|---|---|---|
 | ★ Top pick Honeywell HF09 5,000 BTU Compact Portable Air Conditioner | £269.99 | 5,000 BTU | ~14 m² | 3-in-1: cool, dehumidify, fan | ★ 4.1 | View → |
£269.99
5,000 BTU · ~14 m² · 3-in-1: cool, dehumidify, fan
The verdict from Marcus Bell, home appliance tester
The best choice for a small room. The Honeywell HF09 is built for a small bedroom or home office up to roughly 14 m², and within that brief it is excellent — compact, easy to move and the quietest unit we tested. Ask it to cool a large lounge and it will struggle, but as an affordable single-room cooler it is exactly right.
Cools a small room quickly and tucks away neatly when summer ends.
The HF09 is the right unit if you need to cool a small bedroom or home office up to roughly 14 m². That's exactly what its 5,000 BTU is sized for, and matching the unit to the room is the whole point. It's ideal if you only have one small space to cool, want something easy to wheel around, and don't want to pay for cooling power you'll never use.
It is emphatically not the unit for a large room. Ask 5,000 BTU to cool a big lounge and it will run flat out and still struggle; for a standard room up to 25 m² you want a 9,000 BTU unit like the MeacoCool MC 9000, and for anything bigger the Russell Hobbs 12,000 BTU.
In a small room of around 12 m², the HF09 cools quickly and holds the temperature comfortably. Correctly sized for the space, it reaches the target temperature fast and then cycles gently — which is precisely how a portable air conditioner should behave. Push it into a larger room and that advantage disappears, so the key is honest room measurement.
This is the HF09's quiet strength. It's noticeably more compact and lighter than the 9,000 BTU all-rounders, so wheeling it between a small bedroom and a home office is effortless, and it stores away neatly when summer ends. For anyone short on space, that portability is a genuine, everyday benefit.
At around 62 dB the HF09 is the quietest unit in our comparison. That's still not silent — the compressor is in the room — but for a bedroom it's the most liveable option here, especially with its lower BTU output meaning the fan simply doesn't have to work as hard. If quietness matters most to you, this is the unit to start with, and our quietest portable air conditioners guide explains why.
Controls are simple and the unit is a 3-in-1 with cooling, dehumidify and fan modes. The window kit goes together quickly, and a Honeywell-branded unit comes with the support reassurance you'd expect from an established name.
The HF09's limitations are the flip side of its strengths: 5,000 BTU is too weak for large rooms, and its lower output means it simply can't do what the all-rounders do in a big space. That's not a fault — it's the correct unit for a small room being honest about its limits. If your room is bigger than about 14 m², don't buy this; size up to a 9,000 BTU unit instead.
For a small bedroom or home office up to around 14 m², yes — that is exactly what the Honeywell HF09 is built for. Larger or strongly sun-facing rooms will overwhelm it, so for those you should step up to a 9,000 BTU unit or more.
Mainly price, size and noise. The HF09 is among the cheapest units here, the quietest at around 62 dB, and its compact body is easier to store and move. If you only need to cool a small room, you would be paying extra for BTU you can't use.
Yes. It is compact and on castors, so wheeling it between a small bedroom and a home office is straightforward, and it packs away neatly when summer ends. That portability is a big part of why it suits single small rooms so well.
The Honeywell HF09 is our best choice for small rooms because, within its brief, it does everything right: it cools a small bedroom or office up to 14 m² quickly, it's the quietest unit on test, and it's compact and easy to move. Its only limitation is that it's too weak for large rooms — which is exactly why you should match it to a small space. If your room is bigger, step up to the MeacoCool MC 9000 or the Pro Breeze 9,000 BTU. To be sure of the right size, use our BTU sizing guide and read the buying guide.