8 Best Types of Air Conditioners for the UK Heat Wave

Quick Answer: The best types of air conditioners for the UK heat wave include portable air conditioners, split-system air conditioners, multi-split systems, wall-mounted units, window air conditioners, smart air conditioners and models with heating functions. The right choice depends on your room size, budget and whether you need a temporary cooling solution or a permanent installation. For most UK homes, a correctly sized, energy-efficient air conditioning unit provides the most effective way to stay cool during periods of hot weather.

The UK might not be famous for scorching summers, but recent years have shown that heatwaves are becoming more frequent and intense. When indoor temperatures start climbing, opening a window or switching on a fan often isn’t enough to keep your home comfortable. That’s why more homeowners are investing in air conditioning to stay cool during periods of hot weather.

At WPJ Heating, we’ve seen first-hand how demand for air conditioning has grown as people look for reliable, energy-efficient ways to beat the heat. Whether you’re trying to cool a bedroom for a better night’s sleep, make a home office more comfortable or keep your living room pleasant throughout the day, choosing the right air conditioning unit can make all the difference.

The challenge is deciding which type is best for your home. From portable air conditioners that offer flexibility to permanently installed split systems that deliver powerful cooling, each option has its own advantages.

In this guide, we’ll explore the 8 best types of air conditioners for the UK heat wave, explain how they work and help you choose the right cooling solution for your space, budget and lifestyle.

Why Air Conditioning Is Becoming More Popular in the UK

As summers become warmer, many UK homes struggle to stay comfortable indoors. Modern properties are designed to retain heat during winter, but that insulation can also trap hot air during a heatwave.

Unlike electric fans, which simply move warm air around a room, air conditioning actively removes heat using refrigerant technology. This lowers both the air temperature and humidity, helping you feel cooler much more quickly.

Many modern air conditioners also offer additional benefits, including:

• Improved indoor comfort levels
• Better sleep during hot nights
• Reduced humidity and moisture
• Faster cooling than fans or air coolers
• Energy-efficient heating during winter on selected models

Whether you’re cooling a single room or your entire home, choosing the right system can improve comfort throughout the year.

Choosing the Right Air Conditioner

Before comparing the different types of air conditioners, it’s important to understand BTU, which stands for British Thermal Units. BTU measures an air conditioner’s cooling power, and selecting the correct size is essential for effective cooling and good energy efficiency.

As a general guide:

A simple way to estimate the right BTU rating is to multiply your room dimensions by five.

Choosing a unit that’s too small means it’ll work harder and use more energy, while an oversized unit may cool the room too quickly without removing enough humidity. Matching the BTU rating to your room size will provide the best balance between comfort, performance and running costs.

1. Portable Air Conditioners

A portable air conditioner is one of the most popular cooling solutions during a UK heatwave. They’re easy to set up, require no permanent installation and can be moved from one room to another as needed.

Most portable air conditioning units come with an exhaust hose and window venting kit, allowing hot air to be vented outside through a nearby window. This is essential, as portable units actively cool the room by removing heat rather than simply blowing air around like a fan.

Portable air conditioners are ideal for:

• Bedrooms
• Home offices
• Flats and rented properties
• Temporary cooling during hot weather

Most models can reduce room temperatures by up to 15°C, depending on the room size and outdoor conditions. Running costs typically range from 20p to 60p per hour, with energy-efficient models costing less to operate.

If flexibility is your priority, a portable air conditioner is often the best place to start.

2. Dual-Hose Portable Air Conditioners

A dual-hose portable air conditioner works similarly to a standard portable unit but uses two hoses instead of one. One hose draws fresh air into the system, while the other expels hot air outside.

This design improves efficiency because the unit doesn’t create negative air pressure inside the room. As a result, it delivers faster cooling, maintains more consistent temperatures and generally uses energy more effectively than single-hose models.

Dual-hose units are particularly well suited to:

• Larger living rooms
• Open-plan spaces
• Conservatories
• Homes that regularly experience extreme heat

Although they’re usually more expensive than standard portable air conditioners, they offer better performance for larger spaces and are one of the most effective portable cooling solutions available.

3. Split-System Air Conditioners

If you’re looking for the best long-term solution, a split-system air conditioner is hard to beat.

These systems consist of an indoor wall-mounted unit connected to an outdoor condenser by refrigerant pipework. Because the noisy components are located outside, split systems operate much more quietly than portable units while delivering greater cooling power.

They also tend to be more energy efficient, making them a cost-effective choice for homeowners who want reliable cooling every summer.

Many modern split systems also provide heating during winter, giving you year-round comfort from a single installation.

4. Multi-Split Air Conditioners

If you want to cool several rooms without installing multiple outdoor units, a multi-split air conditioning system is an excellent choice. One outdoor condenser connects to several indoor units, allowing you to control the temperature in different areas of your home independently.

This makes multi-split systems ideal for larger properties, families with different comfort preferences or homes where certain rooms become much hotter than others.

Benefits include:

• Cooling multiple rooms from one outdoor unit
• Individual temperature control
• Improved energy efficiency
• Quiet operation
• A neat, space-saving installation

Although installation is more involved than a portable unit, a multi-split system provides consistent comfort throughout your home while keeping energy use under control.

5. Wall-Mounted Air Conditioning Units

Wall-mounted air conditioners are among the most popular choices for UK homes because they combine powerful cooling with a discreet appearance. Installed high on an internal wall, they distribute cool air evenly across the room without taking up valuable floor space.

Most modern units include features designed to improve both comfort and convenience, such as:

• Remote control
• Timer settings
• Sleep mode
• Quiet operation
• Smart controls via Wi-Fi
• Air filtration

If you’re installing air conditioning in a bedroom, look for a model with a dedicated Sleep Mode. This gradually adjusts the temperature overnight while reducing noise levels, helping you stay comfortable without disturbing your sleep.

6. Window Air Conditioners

Window air conditioners are less common in the UK but can be a practical solution for properties with compatible window styles.

Unlike portable air conditioning units, which require an exhaust hose, a window air conditioner is fitted directly into a window opening. This allows it to vent hot air outside more efficiently, making it generally more energy efficient than a standard portable model.

However, because most UK homes have outward-opening casement windows, installation isn’t always possible. If your property isn’t suitable, a portable or split-system air conditioner is usually the better option.

7. Smart Air Conditioners

Modern air conditioning has become smarter than ever. Many systems now allow you to control your home’s temperature using a smartphone app, voice assistant or programmable schedules.

Smart features help improve both comfort and energy efficiency, ensuring the unit only operates when required.

Look for features such as:

• Wi-Fi connectivity
• Remote control through an app
• Weekly scheduling
• Eco mode
• Automatic temperature adjustment
• Energy monitoring

Being able to cool your home before you arrive is particularly useful during periods of extreme heat, while smart scheduling can also help reduce running costs.

Choosing the Right Cooling Power

Whatever type of air conditioner you choose, selecting the correct cooling capacity is essential. A unit that’s too small will struggle to cool the room, while one that’s too powerful may use more energy than necessary.

As a quick guide:

• 7,000 to 8,000 BTU is suitable for a small bedroom or home office.
• Around 9,000 BTU is ideal for most standard UK bedrooms.
• 12,000 to 14,000 BTU is recommended for larger living rooms and open-plan spaces.

When choosing an air conditioner, also consider ceiling height, sunlight, insulation and how often the room is used. These factors all affect how much cooling power you’ll need.

At WPJ Heating, we always recommend selecting a system based on your home’s layout rather than simply buying the biggest unit available. A correctly sized, energy-efficient air conditioner will deliver better performance, lower running costs and greater comfort during every UK heatwave.

8. Air Conditioners with Heating Functions

Many people are surprised to learn that modern air conditioning units can do more than simply keep your home cool during summer. Many split-system and wall-mounted models also include an efficient heat pump, allowing them to provide heating during colder months as well.

This makes them a smart long-term investment, giving you year-round comfort from a single system.

Benefits include:

• Cooling in summer and heating in winter
• Improved energy efficiency
• Lower reliance on portable heaters
• Consistent indoor temperatures
• Better humidity control throughout the year

If you’re considering a permanent installation, choosing a unit with both heating and cooling functions offers excellent value.

Air Conditioners vs Air Coolers vs Fans

When searching for ways to stay cool during a UK heatwave, you’ll usually come across three main options: air conditioners, air coolers and electric fans. While they all help improve comfort, they work in very different ways.

Air Conditioners

Air conditioners actively remove heat from the room using refrigerant gas, reducing both the temperature and humidity. They can cool a room by up to 15°C, making them the most effective solution during prolonged periods of hot weather.

They’re best for:

• Bedrooms
• Living rooms
• Home offices
• Large spaces
• Anyone wanting reliable cooling

Air Coolers

Air coolers use water or ice packs to create an evaporative cooling effect. They can make the air feel cooler by around 4°C, but they don’t actively remove heat like an air conditioner.

They’re quieter, cheaper to run and suitable for smaller spaces, but they’re less effective during humid weather.

Electric Fans

A fan simply improves airflow by blowing air around the room. While this can help you feel cooler, it doesn’t reduce the actual room temperature.

Fans are inexpensive and cost-effective to run, but during periods of extreme heat, they simply circulate warm air rather than cooling it.

For the best comfort during a heatwave, a properly sized air conditioning unit remains the most effective choice.

Which Air Conditioner Is Right for You?

Choosing the best system depends on your home, budget and cooling requirements.

• Portable air conditioners are ideal for renters or cooling one room.
• Dual-hose portable units provide faster, more efficient cooling.
• Split systems are the best long-term solution for most homeowners.
• Multi-split systems are perfect for cooling several rooms.
• Wall-mounted units combine excellent performance with a discreet design.
• Window air conditioners work well where compatible windows are available.
• Smart air conditioners offer convenient remote control and improved energy management.
• Heating and cooling systems provide year-round comfort from one installation.

At WPJ Heating, we always recommend choosing a system based on your room size, insulation and how you use the space, rather than simply buying the largest unit available.

Conclusion

As UK summers continue to become warmer, investing in the right air conditioning system is one of the best ways to improve comfort at home. Whether you need a portable air conditioner for a bedroom or a professionally installed split system for your entire property, selecting the right unit will help you stay cool while keeping running costs under control.

Our team at WPJ Heating can help you choose the right air conditioning solution for your home, ensuring it’s correctly sized, professionally installed and designed to provide reliable performance for years to come.

If you’re thinking about installing air con before the next heatwave arrives, get in touch with WPJ Heating today for expert advice and a tailored recommendation.