Best Wall-Mounted AC Units in the UK

It’s no secret that UK summers are getting hotter (like, seriously hotter), which is making air conditioning more appealing with each passing year.

And frankly, we’re a long way from building our homes to be better in the heat, because we still want to keep warm in the winter.

So if you’re suffering in the heatwaves, one of your best options is investing in a wall-mounted AC unit. They’re not too intrusive, they’ll keep you cool, and if you get an efficient model, they won’t even cost you that much to run.

You’ll want to know what the best models to buy are of course, which is why we’ve written this guide. We’ll give you our top picks for the best wall-mounted AC units in the UK, all reviewed by our expert team!

Ready to beat the heat and get cool? Find out exactly what size air conditioner you need and get a fixed price in seconds here.

🔑 Key Points:

• Wall-mounted AC units cool individual rooms, not your entire house

• Avoid AC units producing 60 decibels (dB) or more of sound

• Keep an eye out for features such as remote controls or timers

• Some AC units can heat your home as well as keep you cool

What Is a Wall-Mounted AC Unit?

Wall-mounted AC units are, as the name suggests, air conditioning units that hang on your wall. What makes them distinctive however, is that they’re used for individual rooms only; unlike central air conditioning, which is complex to install and much more expensive.

We often call wall-mounted AC units “split systems”, because they’re made from an inside unit, which is what keeps you cool, and an outside unit, which releases the heat drawn from your room.

Is It Worth Getting a Wall-Mounted AC Unit?

Yes, getting air conditioning is worth it, especially considering the fact that UK summers are getting warmer. It was only a few years ago that London hit 40°C, and in 2024, many parts of the UK baked in 35°C of heat. Air conditioning in this country is becoming more like a necessity than a luxury.

AC units aren’t just for keeping you cool these days either – many modern systems can heat, dehumidify, and purify the air. It’s fair to call AC units a year-round upgrade for any home.

Wall-mounted AC units are also extremely efficient, so you’ll not be spending much keeping your home cool. Certainly less than if you purchase portable air conditioning, which might have lower upfront costs, but generally cost more to run and aren’t as effective in lowering temperatures.

Read more:

• How Much Does Air Conditioning Cost in the UK?

The Best Wall-Mounted AC Units in the UK

Here’s a quick list of our picks for the best wall-mounted AC units in the UK:

How We Ranked These Wall-Mounted AC Units

We focused on the key features of wall-mounted AC units that really matter. This includes:

• Performance

• Noise levels

• Cost

• Features

• Warranties

Energy efficiency was an important factor as well – specifically, the Seasonal Energy Efficiency Rating (SEER) of each model.

SEER Explained

SEER is a measure of an AC unit’s cooling over a season and is used to provide a more detailed picture of an appliance's energy efficiency. We typically consider SEER as measuring the AC’s cooling ability over summer, when it’ll be used the most.

You can calculate the SEER by dividing the total cooling output (in British Thermal Units, or BTUs) by the electricity used (in watt-hours) across various summer temperatures.

The higher the SEER of an AC unit, the more efficiently it’ll keep you cool – and essentially, the less you’ll spend on doing so. As a general rule, a good SEER rating for air conditioning is 6.5 and above, which you can roughly translate to energy efficiency ratings of A++ and beyond.

Daikin Sensira 3.5kW (12,000 BTU)

Best for: Smart Features

If you’re going to put your faith in an air conditioning unit, the Sensira range from Daikin is a great choice. Daikin is the world’s biggest manufacturer of air conditioning units, so it’s a fair assumption that it knows what it’s doing when it comes to the technology.

And speaking of technology, the Daikin Sensira is full of it – innovative controls accessed via the easy-to-use Onecta app allow you to fully adjust the Sensira as you see fit. Using your phone, you can precisely change the temperature of the room to your liking.

You’ll still get a physical remote you can use to adjust the air conditioning of course, but what’s ideal about the app is that you can change the temperature from anywhere with an internet connection. Imagine you’re on your way back from work on a sweltering summer’s day – use the Onecta app to ensure your home is plenty cool by the time you get back. That’s pretty clever if you ask us!

Key Specs:

• Cooling & heating: 12,000 (ideal for most UK living rooms)

• Heating up to A+ and cooling up to A++

• Noise levels: 20dB in quiet mode

• Smart controls: Wi-Fi app control via Onecta app

• SEER: 6.5

• Warranty: 7 years

Pros:

• Powerful enough for most UK homes

• Smart features offer deft control options

• Vertical Auto Swing features allows cooling to radiate around the entire room

• Uses R32 refrigerant, which is much better for the environment than synthetic refrigerants

Cons:

• Wi-Fi connectivity might be challenging to set up for some

• The module for Wi-Fi connectivity comes separately and needs to be requested

• Purchasing and installing the 3.5kW model can cost around £2,145, which is quite high

Why We Rate It:

Daikin is a brand you can trust, and the Sensira rage is a great example of this. Smart features, eco-friendly refrigerant, and high efficiency make it an ideal choice for most UK homes.

Read more:

• Portable vs Wall-Mounted Air Conditioners: Which Is Best for UK Homes?

Worcester Bosch Climate 3000i (12,000 BTU)

Best for: All round excellence

Our pick for the best overall wall-mounted AC unit in the UK, is the Worcester Bosch Climate 3000i. It’s got all the power you’ll need to keep cool when the temperature rises, with a 12,000 BTU rating, and it’ll do this with an A++ efficiency rating too. So you won’t need to worry about breaking the bank to stay comfortable in the heat!

And when it’s getting colder outside, the Climate 3000i doubles up as a heat pump, keeping you warm instead. It’s very quiet while it does all this, barely going above 19dB, so you can keep cool and zen at the same time.

If aesthetics matter to you, then you’d be hard pressed to find a better looked wall-mounted AC unit than the Climate 3000i. We think it’s the very definition of sleek and sophisticated, which is no surprise considering how good boilers from Worcester Bosch look.

You can also control your Climate 3000i from your phone with the Bosch HomeCom app, so you’ll have an AC unit with its tech firmly in 2025, as well as its visuals.

Key Specs:

• Cooling and heating: 12,000 BTU

• Efficiency: A++ energy rating

• Noise level: As low as 19dB indoors

• Smart controls: Wi-Fi app control via Bosch HomeCom

• Extras: Built-in air purification – great for allergy sufferers or dusty old homes

• SEER: 7.4

• Warranty: 5 years

Pros:

• Powerful enough for open-plan spaces

• Super quiet even when running on maximum

• You can use it for heating and cooling, giving it year-round value

Cons:

• Installation sets you back around £1,800–£2,200

• Setting up the app can be tricky for non tech-savvy people

Why We Rate It:

This is the wall-mounted AC unit for people who want it all – fast cooling, air purifying, money saving efficiency, and dare we say, dashing good looks to boot.

Its versatility in being able to heat as well as cool your home only gives the Climate 3000i and added bonus.

Mitsubishi MSZ AP

Best for: Exceptionally low noise levels

Keeping cool is all well and good, but you don’t want to sacrifice the noise levels in your home doing so. The Mitsubishi MSZ AP is the AC unit to go for if this is a priority, because it is comfortably the quietest unit we reviewed. It can provide effective air conditioning for your home at just 18dB, which is barely above either a soft whisper or the rustling of leaves.

The MSZ AP doesn’t make any sacrifices in performance either, reaching a very impressive SEER of 7.4. And, if the idea of regularly cleaning your AC unit sounds like a chore, you’ll like the fact that the MSZ AP has a dust-resistant coating.

We particularly appreciate the compact design of the MSZ AP, which helps it blend seamlessly into the room it’s in.

Key Specs:

• Cooling and heating: 12,000 BTU

• Efficiency: A++ energy rating

• Noise level: 18dB

• Smart controls: Wi-Fi functionality, connects to Alexa

• Extras: Double vanes allows better air flow

• SEER: 7.4

• Warranty: 3 years with standard installation, up 5 with accredited installers

Pros:

• The quietest unit we tested (and this includes the outside unit)

• Dust-resistant coating means you don’t need to clean it as much as other units

• Minimal design helps the unit blend in

Cons:

• No dedicated app for controlling the unit

• Might not be as effective at cooling in quiet mode

Why We Rate It:

This is the AC unit dedicated to keeping as low a profile as possible. It’s the quietest we tested and it doesn't scream “look at me”, which in a world of technology all trying to compete for our attention, is a big selling point.

Read more:

• Best Location To Install Air Conditioning UK

Viessmann Vitoclima 232-S (12,000 BTU)

Best for: Energy efficiency

Of every AC unit we’ve reviewed in this article, Viessmann’s Vitoclima 232-S was the most efficient. Its SEER is an industry-leading 9, which effectively means for every £1 you spend on electricity for the unit, it’ll output £9’s worth of cooling.

This puts the Vitoclima 232-S firmly in the A+++ efficiency class – and that’s for both cooling and heating. It looks amazing too, with a high-quality finish to help it complement just about any décor.

You can also control the Vitoclims 232-S via the EWPE Smart app, so you can adjust the temperature wherever you may be, as long as you have an internet connection.

Key Specs:

• Cooling/Heating Capacity: 12,000 BTU

• Energy Efficiency: A+++ rating

• Noise Level: 24dB

• Smart Features: Wi-Fi connectivity for remote control

• SEER: 9

• Warranty: 2 years

Pros:

• The most efficient unit we reviewed

• Effective air purification enhances indoor air quality

• Minimal, stylish aesthetics help it match a range of interior designs

Cons:

• At 24dB, it’s still quiet but not as quiet as other models on this list

• Installation costs range between £1,800–£2,200

Why We Rate It:

Saving money on energy bills is more important than ever, but so is keeping cool in the UK’s rising temperatures. The Vitoclima 232-S is a fantastic response to this growing need thanks to its incredibly high efficiency, which allows it to keep you cool while costing less to run than every other model on this list.

Panasonic Etherea (12,000 BTU)

The Panasonic Etherea AC unit was one of the most interesting models we reviewed here, thanks to its innovative nanoe™ X technology, which purifies the air it uses to keep you cool.

This feature makes use of something called “hydroxyl radicals”, which are abundant in nature and, according to Panasonic, work to “inhibit pollutants, certain viruses, and bacteria.”

Rather impressive if you ask us.

Additionally, you can control the AC unit with your voice (after setting up and connecting to the Panasonic Comfort Cloud App). The Panasonic Etherea works with Amazon Alexa too.

You’ll get plenty of efficiency as well, with a SEER of 8.5.

Key Specs:

• Cooling/Heating Capacity: 12,000 BTU

• Energy Efficiency: A+++ rating

• Noise Level: 30dB

• Smart Features: Wi-Fi control via the Panasonic Comfort Cloud App

• SEER: 8.5

• Warranty: 3 years

Pros:

• Actively purifies the air circulating around the rooms its installed in

• Comes in various finishes to match different aesthetics (white, silver, and graphite)

• Decent range of power outputs available – 2.05kW to 7kW

• Easily controlled with the Panasonic Comfort Cloud App

Cons:

• Could be quieter – 30dB is the highest on this list

• Etherea AC units can cost a premium

Why We Rate It:

This is the AC unit you pick if you want best-in-class air purification on top of highly effective cooling. It’s also a great choice if you don't want the standard white colour of most AC units, because you can choose from white, silver, or graphite.

So You’ve Picked an AC Unit… What Next?

Your wall-mounted AC unit will require professional installation by an F-Gas certified engineer. Unfortunately, you can’t DIY here, unless you’re willing to risk what could end up being a very costly mistake.

Here’s a breakdown of what to expect:

• Process – Your engineer will mount the indoor unit, install the outdoor condenser, and connect them with pipes. This’ll take 4–8 hours for a single unit.

• Cost – It’s around £1,500–£2,500 for a single-split system, or £6,000–£9,000 for multi-split. Get a fixed-price quote from Heatable’s AC installation service.

• Planning Permission – You don’t usually need this for domestic AC units, but check with your local council if you’re in a listed building or conservation area.

• Portable units? Just plug them in and vent the hose through a window. But as we’ve said, they’re noisier, less efficient, and a bit of a faff.

Next Steps For Your AC Journey:

When planning to install air conditioning for your home, there are several important factors to consider. Make sure to refer to the following guides to help you make informed decisions:

• What size AC do you need?

• Portable vs wall mounted air conditioners

• Split system air conditioning

• Air conditioning for bedrooms

• What is an air conditioning condenser unit?

• Can I have air conditioning and a gas boiler?

• What is BTU?

To dive deeper into these topics, head over to our advice section, check out our YouTube channel for informative videos.

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