Internal Water Cooled Condenser Air Conditioning For Apartments In London


The prices shown below are lead-in prices (PER ROOM) for the complete supply and installation of one of our systems. Please contact us with the approximate dimensions, type and use of the room(s) to be air conditioned and we will be happy to give you an accurate price.
Depending on your budget and the layout of your apartment, sometimes by air conditioning just one room, it is enough to neutralise the heat build up within the whole apartment. We are happy to advise you of the best and most cost effective solution for you.

3.5kw (12,000 BTU/h)
DC Inverter Water Cooled (Internal Condenser)
Air Conditioning System

Supplied and installed
£4,650 + VAT per room
No hidden extra costs

(£5,580 inc. of VAT)


5.3kw (18,000 BTU/h)
DC Inverter Water Cooled (Internal Condenser)
Air Conditioning System

Supplied and installed
£5,250 + VAT per room
No hidden extra costs
(£6,300 inc. of VAT)


7kw (24,000 BTU/h)
DC InverterWater Cooled (Internal Condenser)
Air Conditioning System

Supplied and installed
£5,650 + VAT per room
No hidden extra costs
(£6,780 inc. of VAT)


Utilising the very latest energy-efficient DC inverter technology, our water-cooled internal condenser air conditioning systems allow you to reach your desired room temperature and keep it constant when the external temperature changes.


Providing a high level of comfort, low noise and cost effective installation, our water cooled internal air conditioning systems provide many benefits whilst cooling your property. These include:

  • Installation in just one day by our specialist FGAS refrigeration engineers
  • The ability to air condition multiple rooms – using just one internal condenser we can either cool one room or indeed cool multiple rooms, depending on the cooling needs of you and your property
  • No outside unit – providing the solution to stringent property restrictions and apartments with limited exterior space, everything is contained internally with our solutions
  • Energy-efficient DC inverter technology provides you with a significant reduction in energy consumption when compared to non-inverters and comparable to the very latest conventional AC systems where you are able to have an external condenser.
  • Compact design – The smallest and most energy-efficient condensers, designed and built by us, without compromise, for London apartments
  • Very quiet operation
  • Ducted room units available
  • Provides cooling simply by being plumbed into your property’s cold water supply, just like a dishwasher or washing machine
  • No pipe work on show
  • Extensive maintenance programme available with full parts back-up
  • A bulletproof 5-year parts and labour warranty


Our internal condenser water cooled air conditioning solutions have been specially designed and developed for apartments & listed buildings in London where you cannot have an outside condenser.

  • Everything is enclosed in your property
  • No outside access required
  • Ideal for retro fitting in apartments and listed buildings
  • Easily concealed condensing unit
  • ‘A++’ rated for Energy Efficiency
  • Energy efficient DC inverter technology
  • The latest environmentally friendly R32 refrigerant
  • We can air condition up to three rooms from one compact multi-split internal condenser
  • Different room unit options
  • Great for home-workers
  • Dehumidifies rooms in cooling mode
  • i-FEEL closer-to-you temperature control as standard on all DC inverter systems
  • No outside condenser

You Can have a beautifully cool apartment in one day!

In Central London, you will not be able to drill holes in exterior walls or install an external condenser. Cool You UK is here to help you!

We are the London experts for internal water-cooled air conditioning (Cool You are the true specialists since 2006, it's all we do.) We have installed hundreds of our internal systems all around the city. Our fully trained F-Gas certified engineers know the best way to install a water-cooled air conditioner in your home.

Find out more below, or contact Cool You today for a free site survey, to make an enquiry or request a callback.

What actually is a water-cooled internal condenser air conditioning system?

With most London apartment buildings, you are not permitted to use external condensers or make penetrations through the exterior walls of the building. Our internal water-cooled air conditioning systems are a no-compromise solution for fully-fledged air conditioning where you cannot have an external condenser box.

It's All On The Inside!

Our fully  internal solution includes a whisper-quiet room unit (fan coil). This is installed in the room that's going to be air-conditioned. We typically specify a wall-mounted unit for a retrofit installation. It can also be a concealed ducted unit, which is usually used during complete home refurbishments. The room units are very sleek and neutral, so it will not clash with your colour scheme.

No Visible Pipework - No Ugly Box On The Outside

The refrigeration pipework runs from the room unit typically into the ceiling void, so it is concealed, to the condenser box. In a conventional system, this is the ugly box on the outside. With our system, the condenser is on the inside, out of sight in your apartment. In most cases, we use the utility space or under a kitchen counter, where it is hidden from view, but close to the required services. The location will be discussed with you during a site survey.

Unlike a conventional system, our internal condensers use water to dissipate the heat in a controlled and efficient manner - this has allowed us to design a condenser that is a fraction of the size of an external air-cooled box. Our internal condensers are compact and incredibly quiet - you won't even know they are running.

A Whisper Quiet, Efficient And Practical Solution

Apart from the obvious benefits of our fully internal air conditioning systems, maintenance is straightforward. You won't have to worry about somebody going to the outside of your property in bad weather, or getting permissions to get on a roof. Also, there will be absolutely no disruption to your neighbours. There will be nothing on the outside for them to complain about, either visually, or from noise. Your outside space is valuable and compact, so you don't have to worry about having a large box taking up space.

With our system, the condenser is kept at a constant internal temperature as opposed to an external box. The efficiency (and running costs) of an external condenser can be compromised by external temperatures. In sweltering weather, the sun can be beating down on an external condenser preventing the efficient dissipation of heat. This does not happen with our internal condensers - they just tick along quietly and efficiently.

No Compromise - Just Great Air Conditioning

Our systems are not a compromise in any way over a conventional system. A Cool You fully internal water-cooled air conditioning system will cool and dehumidify with efficiency and will filter the air in your apartment, leaving you with a cool, comfortable home.

A whisper-quiet room unit in an open-plan kitchen/living/dining area within a modern London apartment.
A ducted room-unit, installed in a London apartment during a refurbishment of the grade II listed apartment building.

We’re Rated Excellent on TrustPilot

Excellent sales and after sales service I must say I really appreciate the good quality service you guys provide. Please keep it up. Thanks very much, I was satisfied as usual. You guys always turn up when I call your help lines and your technicians are always ready to do everything to make things better for the benefit of the customer. This is unlike several vendors or contractors I’ve met. After sales customer service is fantastic. I Like the culture of excellence. You guys are a class apart. Please keep it up. Kudos to your entire team. Well done.
6. July, 2021.
My first experience of Cool You was a good one. Tommy, their youthful engineer (I'm 73) took the time to explain their system that I had taken over in my new apartment so that I could use my three units safely and efficiently. Further back-up came from head office who sent my operational instructions that had not been left by the previous owners. I feel confident that any difficulties that I might encounter in the future will be dealt with kindly and efficiently.
Nigel Hodd
5. July, 2021.
Really happy with the thorough on site assessment of our flat, which compared to other visits by another team, was streets ahead in being able to answer my queries and give me the reassurance we needed to proceed. The installation was on time and effortless, and we love our new air con unit! We can barely hear the condenser during it's operation, and we can chill a previously inhospitable sweat-box of a room in the summer in under a couple of minutes.
Omer Mustafa
3. July, 2021.
Excellent service and equipment I'm writing this on behalf of my parents. At the beginning of June we had air conditioning installed in the lounge by Ultra Cooling. Paul Kibble and did the job. It was a very technical assembly and they were obviously experienced experts. Their specialist equipment ensured there was not a speck of dust or cleaning afterwards. The system works well and from our experience we would definitely recommend them and use them again 10/10
Clare Dew
30. June, 2021.
A Cool Summer I have recently had a Cool You aircon system installed in my London apartment. My living room has floor to ceiling glazing with a southerly aspect and in the Summer it used to become unbearably hot and humid. Not anymore! This water-cooled system now keeps it at the temperature I choose and my apartment living has been transformed. I would highly recommend this aircon system. The initial cost may seem high but be assured the product is first rate and Cool You are highly professional in the service they provide with their speedy and tidy installation procedures, their subsequent aftercare, and the efficient and courteous way they deal with their clients.
23. June, 2021.
A great product and team - pre and post sales Excellent product and customer care. Continuous support and responsive team who don’t drop you the second they’ve made the sale, but genuinely care about your considerations and any subsequent servicing. Very understanding and accommodating over the Covid period.
Tobias Lee
21. June, 2021.
Easy, friendly, no extras, no fuss. The site visit was timely, sensible, quote followed quickly, dates given were all met. The installation was just over a half day (2 rooms, one condenser). No mess left. Product works well (for the last 3 days since installation). All easy, friendly, no extras, no fuss.
5. June, 2021.
Excellent service visit . The engineer was on time , courteous and respectful of my home . A company to be recommended to ours . Thank you
4. June, 2021.
Expensive but works flawlessly The solution is expensive but you get what you pay for - and what you get is a very efficient air conditioning system, installed professionally and to a high standard. My property has 2 bedrooms located in the loft (one of which is south facing) which can get uncomfortably hot in the summer. After the last year's summer and having to deal with a noisy and rather fiddly (especially with Velux windows involved) portable aircon I decided to bite the bullet and get Cool You to install a water cooled solution in my property (external compressors were not allowed by the freeholder). I have to say that it's more than adequate to cool (and maintain) the entire upstairs to a pleasant 22C in a matter of minutes which is a huge quality of life improvement. The installation was also very efficient and done professionally - the installers arrived punctually at 8am and were done by lunchtime - I honestly did not expect such efficiency given the rather unusual layout of my property and what I though could have been challenges with finding the right spot to install the condenser. They installed the it neatly in the loft (I initially thought there might be issues with water and power supply but I shouldn't have worried as they somehow did their magic and got water, power and waste sorted) and two wall-mounted units in the bedrooms. There was indeed no mess and minimal disruption, which I was initially rather sceptical about despite the claims on their website. So far the system does the job although I can't comment on the running costs as it's only been a few weeks since the installation. Overall a good experience, job done to a very high standard and delivering on their promise. Yes, it's not cheap but I wouldn't think twice about spending the money given how much more liveable my property now is in the current hot weather.
3. June, 2021.
Great a/c solution in a flat Really neat a/c system with no external fittings needed so it was the ideal solution for our flat and I couldn’t be happier. Prompt service and helpful fitters.
Nigel in London
1. June, 2021.


Call us on  0207 043 2275 or REQUEST A CALL BACK MAKE AN ENQUIRY