The best air conditioners to buy in 2021

28 March 2021

air conditioner

Beat the heat with our pick of the best portable air conditioners to buy in the UK.

You might think it unnecessary to buy an air conditioning unit in the UK but on stifling hot days and nights, a portable AC system can be an invaluable addition to your home. And with summer temperatures continuing to rise and more and more people working from home, you’ll want to ensure you’re equipped to keep you and your family cool and comfortable throughout the summer months.

Of course, you’re never going to need an air conditioning unit in the middle of winter in the UK, which is why most air conditioners sold here are portable units or double up as heaters. But with so many to choose from and important factors like running costs, noise levels, price and size to consider, it can be tricky to pick the right one. We’ve put together a selection of the best air conditioners to help you beat the heat, including tried-and-tested models recommended in the Mumsnet forums.

Here are the best air conditioners to buy in 2021.

1. Best overall air conditioner: De'Longhi PAC AN112 Silent Air Conditioner

1. Best overall air conditioner: De'Longhi PAC AN112 Silent Air Conditioner

Every air conditioner uses a motor called a compressor to shift the heat out of your house through an outlet hose, which most people stick out of the window. So the better the compressor you buy, the better your air conditioning will be – and that’s why an established brand like De’Longhi is our best overall pick.

Because they use a motor, all compressors make noise, but the PAC AN112 is quieter than most at 50 decibels (for context, the average conversation is about 60 decibels). It’s A+ energy rated, doubles up as a dehumidifier, has a remote control, and is rated at 11,000 ‘BTUs’ – meaning it can cool a room up to 100m³ (there’s more info on what this measurement means in our buyers guide below). There are cheaper models, but if you can afford it, the De’Longhi is a great choice.

Key specs

  • BTU (British Thermal Unit) rating: 11000 BTUs
  • Max room size: 100m³
  • Weight: 30kg
  • Dimensions: 45 × 39.5 × 75cm
  • Features: 50dB
Buy now from Amazon

2. Best budget air conditioner: Arlec Portable Air Conditioner

“I have an Arlec one from Homebase I bought a few years ago. Honestly, it’s the best thing I’ve ever bought and cools the bedroom wonderfully. I vent it out through the ensuite window and have one of the window attachments on there so it's more effective.”

2. Best budget air conditioner: Arlec Portable Air Conditioner

This Arlec portable air conditioner has two speed settings to choose from and packs an 8000 BTU punch, so it will cool a room up to approximately 32 square metres (although the manufacturer recommends it for ‘small’ rooms).

The 24-hour timer function is handy for overnight use and it doubles up as a dehumidifier too. At 22kg, it’s lighter than many on the list so it shouldn’t be too much trouble to pack away in the winter when it’s not needed.

Key specs

  • BTU (British Thermal Unit) rating: 8000 BTUs
  • Max room size: Small (approximately 32m sq)
  • Weight: 21kg
  • Dimensions: 86 × 35 × 38cm
  • Features: A rated; two speed settings; 65dB; 24-hour timer; remote control
Buy now from Homebase

3. Most portable air conditioner: Pro Breeze 4-in-1 Portable Air Conditioner with Window Kit

“We have just recently bought this one after suffering three horrendous summers in our new build. The temp was 28C and this brought it down to 21C then it just uses the fan. It has auto settings so turns back on when the room reaches over whatever temp you set it to! It is quite loud but then most of them are!”

3. Most portable air conditioner: Pro Breeze 4-in-1 Portable Air Conditioner with Window Kit

The Pro-Breeze 4-in-1 air conditioner is packed with features (automatic and manual air con, a fan mode and a dehumidifier) and at just 64cm tall it’s one of the most compact units on our list. While it’s already relatively light by air conditioner standards (22kg), the castor wheels on the bottom make it easier to move around, so you can cool more than one room.

It can take the temperature all the way down to a positively chilly 15 degrees and comes with an included window kit to help you fit the outlet hose snugly to your window, to make the unit work as efficiently as possible.

Key specs

  • BTU (British Thermal Unit) rating: 7000 BTUs
  • Max room size: Small/medium
  • Weight: 22kg
  • Dimensions: 31 × 31 × 64cm
  • Features: Energy A rated; window mount; remote control; sleep mode; oscillating fan
Buy now from Amazon

4. Best mid-range air conditioner: Igenix IG9901 3-in-1 Portable Air Conditioner

4. Best mid-range air conditioner: Igenix IG9901 3-in-1 Portable Air Conditioner

With 9000 BTUs of power, the Igenix IG9901 portable air conditioner is ideal for rooms ranging up to 20 square metres. It’s the lightest on our list at 17.4kg, and also has a carry handle to move it from room to room.

It’s a breeze to get the settings right, with a touch LED display, and a remote control to use from across the room if it’s too hot to peel yourself off the sofa. One thing to bear in mind is the outlet hose is only 1.5 metres, so think about where in the room you can place the unit.

Key specs

  • BTU (British Thermal Unit) rating: 9000 BTUs
  • Max room size: Up to 20m sq
  • Weight: 17.4kg
  • Dimensions: 34.8 × 32 × 68cm
  • Features: Remote control; 24-hour timer; 1.5m exhaust hose; three speeds, two-year warranty
Buy now from Amazon

5. Best quiet air conditioner: Olimpia Splendid Dolceclima Portable Air Conditioning Unit

“Thanks to this air conditioner, my room was 17 degrees all night. It’s noisy but you do get used to it.”

5. Best quiet air conditioner: Olimpia Splendid Dolceclima Portable Air Conditioning Unit

The Italian-made Olimpia Splendid Dolceclima has a mighty 12000 BTUs of cooling power and the manufacturer states it’s more like a 14000 BTU unit thanks to its ‘bluewave’ technology which tweaks the settings as it runs.

This power doesn’t come at the cost of increased noise levels, thankfully. The Dolceclima will run as low as 38 decibels on its quiet setting, making it much quieter than many other less powerful air conditioners.

It’s at the higher end of the price scale, but you get three fan speeds to choose from, automatic condensation removal (so no tank to empty) and auto, sleep, timer and turbo functions.

Key specs

  • BTU (British Thermal Unit) rating: 12000 BTUs
  • Max room size: 35m sq
  • Weight: 28.5kg
  • Dimensions: 46 × 76.2 × 39.6cm
  • Features: A+ Energy rated, 38-49dB
Buy now from Amazon

6. Best air conditioner for the bedroom: Amcor SF8000E Portable Air Conditioner

“We have this one – It was fantastic in the height of summer last year!”

6. Best air conditioner for the bedroom: Amcor SF8000E Portable Air Conditioner

The no-fuss Amcor SF8000E is a three-in-one unit that offers cooling air conditioning, a fan setting and a dehumidifier function. It comes with a 12-month warranty for peace of mind too.

Its 7000 BTUs will cool smaller rooms up to 18 square metres in size, so it should be fine for most bedrooms, and it can run more quietly than many other models. You might find that 38 decibels is quiet enough to allow you to drift off with it running on a really hot night.

Key specs

  • BTU (British Thermal Unit) rating: 7000 BTUs
  • Max room size: Up to 18m sq
  • Weight: 21kg
  • Dimensions: 32.8 × 30.5 × 67.8cm
  • Features: 2.06w; caster wheels; 38dB on low setting
Buy now from Appliances Direct

7. Best desktop air conditioner: JMLChillmax Air Personal Space Air Cooler and Humidifier

7. Best desktop air conditioner: JMLChillmax Air Personal Space Air Cooler and Humidifier

You will probably have noticed that even budget air conditioners aren’t the cheapest with many starting at £200, so this cheap and cheerful personal air cooler is worth considering if you just want to cool yourself and not a whole room!

Ok, so it’s not technically an air conditioner, it evaporates cool water and uses a fan to give you a cooling breeze. But if you put it on your desk or bedside table you should feel the benefit – just remember it’s strictly for individual use in close range.

Key specs

  • BTU (British Thermal Unit) rating: n/a
  • Max room size: Personal use only
  • Weight: 1kg
  • Dimensions: 18 × 24 × 16cm
Buy now from Amazon

8. Best air conditioner for bigger rooms: AEG ChillFlex Pro AXP34U338CW

8. Best air conditioner for bigger rooms: AEG ChillFlex Pro AXP34U338CW

AEG’s ChillFlex Pro will cool a room measuring up to 45 metres squared, so it could be a great option to keep the whole family cool in the living room.

On the whole, air conditioners aren’t renowned for their beauty, but this model is ever so slightly more stylish than some. It has an A energy rating and it uses a special type of refrigerant gas called R290, which is more environmentally friendly than some budget models, so you shouldn’t feel as guilty when you’re chilling out.

A couple of other things to note: Its 1.2 metre exhaust hose is on the short side and a window kit isn’t supplied, so you’ll need to buy one separately.

Key specs

  • BTU (British Thermal Unit) rating: 11000 BTUs
  • Max room size: 100m³
  • Weight: 30kg
  • Dimensions: 45 × 39.5 × 75cm
  • Features: 50dB
Buy now from John Lewis

9. Best smart air conditioner: KYR-45GW/AG-H Mobile Air Conditioning Unit

“I got it about six years ago and it’s still going strong! It doesn’t eat up electricity either (I’m on a meter so it’s easy for me to see). It also came with a panel for the window so I didn’t need to buy anything separately. I couldn’t be without it now. I’m not too bothered about the noise as it’s white noise and an added bonus is that it covers the noise of neighbour's parties!”

9. Best smart air conditioner: KYR-45GW/AG-H Mobile Air Conditioning Unit

Have you ever told Alexa you’re too hot? Well, the KYR-45GW could be the air conditioner for you – it integrates with the Amazon (or Google) voice assistant to make it a breeze to get the temperature in your house just right.

It is a powerful unit too. The 14000 BTUs will cool a room measuring up to 35 metres squared, and the two-metre outlet hose and included window mounting kit give you a bit more flexibility than some other models. You might even decide to leave it out all year – it can heat a room in winter too.

Key specs

  • BTU (British Thermal Unit) rating: 14000 BTUs
  • Max room size: 35m sq
  • Weight: 28kg
  • Dimensions: 44 × 33.5 × 71.5cm
  • Features: 4.1kw, A energy rated; Alexa and Google Assistant compatible
Buy now from Aircon Centre

What is an air conditioner?

To keep things really simple, an air conditioner is a device that can help you get your house to the ideal temperature to keep you and your family comfortable.

As the climate in the UK only tends to get hot enough to warrant using one in the summer months, this list concentrates on portable units that you can pack away in the winter (or use as a heater when it gets cold). These work by using a compressor (essentially the same technology you get in your fridge) to extract heat from the air and pump it outside (usually through a hose dangling out the window).

How does an air conditioner work?

The compressor unit in an air conditioner forces warm air over cool ‘refrigerant’ gases, which can be evaporated over and over again to absorb heat. This means they can be quite power hungry (keep an eye out for the ‘energy rating’ from A++ down to G) and the gases used have an environmental impact too (even though they don’t use the really damaging CFCs that used to damage the ozone layer).

How to choose the best air conditioner

The most important thing is to keep an eye on the BTU rating of your air conditioner. This measurement stands for ‘British Thermal Unit’ and lets you know how big a room your AC will be able to cool.

As a rule of thumb, a unit with a higher BTU rating will cost a bit more, and could be more expensive to run, so there’s not much point in getting one that is more powerful than you need. And because they all need to get rid of the heat they have extracted from the air, make sure there is somewhere you can put it in your room that is close enough to a window or other outlet.

The other thing to bear in mind is that because air conditioners need a motor to power the compressor and/or a fan, they all make a bit of noise. Have a think about where you will use it and consider a quieter model if you’re going to be using it in the bedroom.

What are the different types of air conditioner?

Our list looks at portable air conditioners, as these are best suited for the British climate. They can be packed away in the winter months when not in use.

If you’re researching elsewhere on the web, you might also see integrated or split-type air conditioners – these are more permanent (and more expensive) units, which probably aren’t worth considering for most homes in the UK.

What’s the best air conditioner? (overall winner)

The De’Longhi PAC AN112 is the best air conditioner to buy in the UK in 2021. This established brand has a good reputation for the quality of its manufacturing, so the workhorse of the unit – the compressor – should work effectively in keeping your house cool.

How we chose our recommendations

Because we know that there’s nothing like a real recommendation from a real parent, we first headed to the Mumsnet forums to find out which air conditioners discerning Mumsnet users had bought. We compiled a list of air conditioners they recommended, noting how effective they found them, and whether they were particularly good for any certain needs.

We then did some research across the wider web, looking at which air conditioners had won accolades or been featured in ‘best buy’ lists across websites and print media, and what customers’ reviews said about them.

Having collated all that information, we picked the air conditioners we thought would make the best buys in several interest categories.

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