Blimey, UK summers are turning up the heat, aren’t they? With temperatures smashing records - hitting a scorching 40.3°C in 2022 - staying cool at home is no longer just a nice-to-have; it’s a must.
- What Is a Split System Air Conditioner?
- How Does It Work? The Refrigeration Cycle Explained
- Pros and Cons of Split System Air Conditioners
- Why Are Split Systems So Popular in the UK?
- Comparing Split Systems to Central Air Conditioning and Heat Pumps
- Installation and Legal Considerations in the UK
- Is a Split System Right for Your Home?
Enter split system air conditioners: the sleek, energy-savvy heroes transforming British homes into cool oases (and cosy retreats in winter, too).
At Heatable, we’re here to unpack the magic behind these clever systems, reveal why they’re popping up in more British homes, and help you decide if they’re the ticket to your perfect home climate.
Let’s dive in!
Key Points:
Split system air conditioners consist of an indoor and outdoor unit connected by pipes, using a refrigeration cycle to cool or heat rooms.
The indoor unit absorbs heat from the room, while the outdoor unit releases it, making the system efficient and quiet.
UK adoption of air conditioning has risen, with temperatures hitting 40.3°C in 2022, driving demand for home cooling solutions.
Split systems are energy-efficient, cost-effective, and versatile, with modern features like remote control and Wi-Fi connectivity.
Professional installation is essential to meet UK regulations and ensure optimal performance.
What Is a Split System Air Conditioner?
A split system air conditioner is a ductless cooling (and often heating) solution designed to regulate the temperature in specific rooms or areas.
Unlike traditional central air conditioning, which relies on a network of ducts, split systems are simpler and more flexible. They’re made up of two main components:
Indoor Unit: Mounted on a wall inside your home, this sleek unit contains the evaporator coil, fan, and air filter. It’s designed to blend into your decor while quietly delivering cool or warm air.
Outdoor Unit: Positioned outside, this unit houses the compressor, condenser coil, and fan. It does the heavy lifting, releasing heat absorbed from inside your home.
These units are connected by insulated copper pipes that carry refrigerant, allowing the system to transfer heat efficiently.
The result? A cool, comfortable room without the noise or energy waste of older systems.
How Does It Work? The Refrigeration Cycle Explained
Split system air conditioners operate using a refrigeration cycle, a clever process that moves heat from inside your home to the outdoors.
Here’s a simple breakdown of how it happens:
Heat Absorption Indoors: Warm air from your room is drawn into the indoor unit, passing over a cold evaporator coil filled with refrigerant. The refrigerant absorbs the heat, cooling the air, which is then blown back into the room by a fan.
Refrigerant Circulation: The now-warm refrigerant travels through copper pipes to the outdoor unit.
Heat Release Outdoors: In the outdoor unit, the compressor pressurises the refrigerant, making it hot. This heat is released into the outside air through the condenser coil, aided by a fan.
Cycle Repeats: The cooled refrigerant returns to the indoor unit to start the process again, maintaining your desired temperature.
This cycle is highly efficient, and many modern split systems can reverse it to provide heating in colder months, making them a year-round solution. Plus, features like air filters improve indoor air quality by trapping dust and pollen.
Pros and Cons of Split System Air Conditioners
To help you decide if a split system is right for you, here’s a quick look at its strengths and drawbacks in a concise table.
Pros | Cons |
Easy to install, no ductwork needed | Higher upfront cost (£1,500–£4,000/unit) |
Energy-efficient with inverter tech | Best for specific rooms, not whole homes |
Quiet indoor operation | Requires regular maintenance (£100–£200/year) |
Stylish, compact design | Outdoor unit needs space, may not suit all properties |
Heats and cools year-round | Professional F-Gas installation mandatory |
Why Are Split Systems So Popular in the UK?
The UK isn’t exactly known for scorching summers, but recent years have seen record-breaking heatwaves, with temperatures soaring to 40.3°C in 2022.
As a result, air conditioning is no longer a luxury - it’s becoming a necessity. Here’s why split systems are winning over UK homeowners:
Rising Demand: Home air conditioning adoption is on the up, with multi-split systems (one outdoor unit connected to multiple indoor units) becoming the most common choice due to their efficiency and flexibility.
Energy Efficiency: Split systems use inverter technology, which adjusts cooling output to match the room’s needs, reducing energy bills compared to central systems.
Quiet Operation: With noisy components housed outside, indoor units are whisper-quiet, perfect for bedrooms or home offices.
Aesthetic Appeal: Sleek, wall-mounted indoor units blend seamlessly with modern interiors, unlike bulky portable units.
Smart Features: Many systems come with remote controls, timers, and Wi-Fi connectivity, letting you control your climate from your phone.
The UK’s push for energy-efficient solutions also aligns with split systems, as they avoid heat loss through ducts and offer high Seasonal Energy Efficiency Ratios (SEER).
“A SEER rating tells you how energy-efficient an air conditioner or heat pump is - kind of like miles per gallon, but for cooling. The higher the SEER, the less it costs to run and the more you save on energy bills.” - Patrick Garner, Gas Safe Engineer.
For eco-conscious homeowners, some units even use propane (R290), a low-global-warming-potential refrigerant, backed by the European Commission for small split systems.
Comparing Split Systems to Central Air Conditioning and Heat Pumps
To help you choose the right system, let’s stack split systems against central air conditioning and heat pumps. Each has its strengths, but your home’s size, budget, and needs will tip the scales.
Below is a table comparing key factors like cost, heating/cooling ability, and more, tailored to UK homes.
Feature | Split System | Central Air Conditioning | Heat Pump (Air Source) |
Cost (Install) | £1,500–£4,000/unit | £10,000–£20,000 | £7,000–£14,000 |
Running Cost | Low (£100–£300/year) | High (£500–£1,000/year) | Very low (£200–£400/year) |
Cooling | Great for zones (2–12 kW) | Whole-home (10–30 kW) | Good (5–15 kW) |
Heating | Efficient to -15°C | Limited, needs separate system | Excellent, primary heat source |
Efficiency | High (SEER 6.0–8.5) | Moderate (SEER 4.0–6.0) | Very high (COP 3.0–4.0) |
Funding | No | No | |
Best For | Small/medium homes, flats | Large homes with ducts | Eco-focused whole-home |
Notes: Costs are 2025 UK estimates. Heat pumps may qualify for £7,500 Boiler Upgrade Scheme grants. Running costs vary by usage and energy prices.
Installation and Legal Considerations in the UK
Installing a split system air conditioner is straightforward, but it must be done by a professional F-Gas-qualified engineer to comply with UK regulations.
The process involves mounting the indoor and outdoor units, connecting them with pipework, and ensuring proper sealing to prevent leaks.
For systems over 12 kw, a TM44 inspection is required every five years to verify energy efficiency and safety.
Most domestic installations don’t need planning permission, provided the outdoor unit meets criteria like being over a metre from the property boundary and not exceeding 0.6m³ in volume. However, always check local regulations, especially for listed buildings or commercial properties.
At Heatable, we recommend budgeting for both the unit and installation costs. While the upfront price might seem steep, the long-term savings on energy bills make it a smart investment. Regular maintenance, like cleaning filters and checking refrigerant levels, keeps your system running smoothly and efficiently.
Is a Split System Right for Your Home?
Before investing, consider your needs:
Room Size: Ensure the system’s British Thermal Unit (BTU) rating matches your room’s square footage for optimal cooling.
Aesthetics: Choose a unit that complements your decor, with options for wall, ceiling, or concealed installation.
Budget: Factor in purchase, installation, and maintenance costs, but expect savings on energy bills over time.
Split systems are ideal for homes without ductwork, offering targeted cooling and heating for individual rooms (like bedrooms) or multi-room setups.
They’re also scalable - additional indoor units can be added to an existing outdoor unit if your needs grow.
Stay Cool with Heatable
As UK summers heat up, split system air conditioners offer an efficient, stylish, and versatile way to keep your home comfortable.
With their quiet operation, energy-saving tech, and smart features, it’s no wonder they’re becoming a go-to choice for British households.
Ready to beat the heat? Get in touch with Heatable for expert advice and professional installation to find the perfect cooling solution for your home.
Stay cool, Britain!
