Is an Air-to-Air Heat Pump the Right Choice for You?

Written-by

Janet Richardson

Reviewed-by

Richard Burdett

Updated on

Jul 20, 2026

Is an Air-to-Air Heat Pump the Right Choice for You?

Interest in air-to-air heat pumps was already increasing before the first heatwave of the year hit the UK in May. Since then, the UK has experienced record June temperatures, with a provisional maximum of 37.7°C recorded at Lingwood in Norfolk. One of the main reasons air-to-air heat pumps are expected to become more popular is that they can both heat your home in winter and cool it during the summer. With UK summers becoming hotter while our winters still require reliable heating, these systems can provide year-round comfort from a single installation.

Modern air-to-air heat pumps use the same technology found in reversible air conditioning systems, allowing them to both heat and cool your home providing an efficient all-in-one solution. They are available as compact single-room units or larger multi-room systems with independent temperature control for each space.

By combining heating and cooling in one system, air-to-air heat pumps can help lower running costs, reduce reliance on conventional central heating and cut carbon emissions. They also allow you to keep your existing boiler for hot water, making them an attractive option for many households looking to improve comfort and energy efficiency. 

Air-to-Air vs Air-to-Water Heat Pumps Comparison Table

Air-to-air and air-to-water heat pumps both extract heat from the outside air, but they work in different ways and suit different properties. The table below highlights the main differences to help you decide which system may be the better fit.

Pros and Cons of Air-to-Air Heat Pumps

Pros

• Superior Energy Efficiency Compared to Other Systems: Air-to-air heat pumps are among the most efficient heating systems available. Rather than generating heat by burning fuel, they move heat from the outside air into your home. Their efficiency is measured using the Seasonal Coefficient of Performance (SCOP), which shows how much heat the system produces over an average heating season compared with the electricity it consumes. Most modern air-to-air heat pumps achieve a SCOP of between 3 and 5, meaning they can deliver between 3 to 5 kWh of heat for every 1 kWh of electricity used. As an example, a home that requires around 12,000 kWh of heat each year could meet that demand using approximately 3,000–4,000 kWh of electricity. This high efficiency can reduce both running costs and carbon emissions while also providing cooling during the summer.
• Great Versatility: Air-to-air heat pumps can both heat your home during the winter and cool it in the summer, providing year-round comfort from a single system.
• Lower Running Costs: Air-to-air heat pumps are highly efficient and can cost significantly less to run than many traditional electric heating systems. By providing both heating and cooling from a single system, they can also reduce the need for separate air conditioning, helping to lower energy bills over the long term.
• Lesser Environmental Impact: Air-to-air heat pumps depend entirely on electricity to operate, which can be sourced from renewable electricity, such as electricity generated by solar panels. This means that they have far less of an environmental impact than traditional heating and cooling systems. These systems are a good choice if you are looking to reduce your carbon footprint. 
• Quicker and less disruptive installation: Air-to-air heat pumps are generally quicker and easier to install than traditional wet central heating systems. They can usually be fitted alongside your existing heating system, so there is often no need to remove or replace radiators or underfloor heating. While improving insulation will always help maximise efficiency, it is not usually a requirement for the installation of an air-to-air heat pump. Apart from mounting the indoor and outdoor units and routing the connecting pipework, disruption is generally minimal, allowing most installations to be completed within a day or two, making them a good choice.
• Easy Temperature Control: Compared with many other heating systems, particularly air-to-water heat pumps, air-to-air systems offer more direct temperature control. Each indoor unit has its own thermostat, allowing different rooms to be heated or cooled independently. For example, you can set your temperature at a comfortable 21 degrees Celsius all year round. In colder months air to air systems pull warm air from the outside and in hotter months they remove indoor heat like an air conditioning system.
• Very Low Maintenance: Another big advantage of air-to-air heat pumps is their low maintenance requirements. Occasional checks and a little basic upkeep are all that’s needed, compared with the often costly and time-consuming maintenance required by conventional heating systems. Filters usually need cleaning every few weeks. Easier maintenance makes air-to-air heat pumps even more attractive as a practical and reliable solution. 
• Improved Indoor Air Quality and Cooling: One of the biggest advantages of an air-to-air heat pump is that it provides efficient air conditioning as well as heating. Most systems also include filters that remove dust, pollen and other airborne particles, while cooling mode naturally helps reduce humidity indoors. Some models offer additional air purification features that can help improve indoor air quality, making them particularly beneficial for people with allergies or asthma. However, they should not be seen as a replacement for good ventilation.
• Suitable for Smaller Rooms: Air-to-air heat pumps can be a good choice for smaller homes and flats, especially when an air-to-water heat pump isn’t suitable. Their outdoor units are usually smaller than the ones used for air-to-water heat pumps. Flats and smaller homes often have limited outdoor space making air-to-air heat pumps a good choice for them. The monobloc system may be suitable for homes where external installation is challenging due to limited access or planning restrictions. 
• May Increase the Value of Your Home: While there is currently limited evidence that air-to-air heat pumps directly increase property values, they may make a home more attractive to buyers. The ability to provide both efficient heating and cooling, together with lower running costs than many conventional systems, can be an appealing feature. As UK summers become warmer and demand for cooling grows, air-to-air heat pumps could become an increasingly desirable addition to many homes.

Cons

• Expensive to Install: Air-to-air heat pump systems can be more expensive to buy if you need to heat or cool many different rooms. Although a single unit is cheap, a whole house air-to-air setup will need indoor blower units in every room. On top of that air-to-air heat pumps cannot heat your tap water, which means you may have to buy a separate water heater. The government’s Boiler Upgrade Scheme provides a more generous grant for air-to-water and ground source heat pumps than air-to-air heat pumps. If you are installing an air-to-water or ground source heat pump you can get a grant of up to £7,500 as opposed to £2,500 for an air-to-air heat pump. The average cost of installing an air-to-water heat pump system in a 3-bedroom house is between £9,000 and £13,000 whereas installing a multi-split air-to-air heat pump system for a 3-bedroom house usually costs between £6,200 and £8,400. These costs do not factor in the government grants available. Currently, there is no VAT to pay on any of these heat pumps. 
• Indoor Units can be Noisier than other Heat Pumps: Air-to-air heat pumps may be noisier than other types of heat pump because the indoor fan units which blow warm or cool air directly into your rooms, operate inside your living space and can be noticeable. Indoor units generally produce about 20 to 40 decibels (dB), which ranges from a quiet whisper to a gentle hum. Outdoor units generate about 40 to 60 dB (similar to a modern refrigerator or standard air conditioner). In contrast, ground-source heat pumps are virtually silent inside the house because their primary compressor components are located entirely indoors, away from living areas.
• May Not Work as Well in Cold Weather: Air-to-air heat pumps work very well in mild to moderate cold (down to about -10°C to -15°C). However, in extreme cold, air-to-water heat pumps (which are the most common type of "air source" system) perform better. This is because air-to-water systems typically run at lower temperatures and use water to slowly distribute radiant heat. In mild conditions, both systems are highly efficient (often producing 3 to 4 kW of heat for every 1 kW of electricity used). However, as the mercury drops, the efficiency and heat output of an air-to-air system will decline noticeably faster than a well-designed air-to-water system. 
• They Take up More Space Indoors: Although air-to-air heat pumps require smaller outdoor units, they need indoor fan coil units similar to air conditioning units, mounted on walls or ceilings in each room you want to heat or cool.
• May Not be as Efficient in Larger homes: Air-to-water heat pumps can be more efficient on a whole-house level if they are paired with underfloor heating, which runs at low water temperatures. The efficiency gap widens when you take into consideration heating your water. Air-to-water systems can heat your water tank highly efficiently. Because air-to-air units cannot heat water, users usually have to rely on standard electric immersion heaters for hot water, which have an efficiency rating of just 1.
• May Require Refrigerant Pipework: You will most likely need to install new pipework when installing multiple indoor units. 
• They Don’t Blow Fresh Air into rooms: Air-to-air heat pumps don’t blow fresh air from outside into your home. They operate by pulling in, filtering, and recirculating the existing air already inside your house, then heating or cooling it and blowing it back out. While the recirculated air is filtered, it is not fresh, oxygen-rich air. Because they do not introduce a new supply of outdoor air, you will still need to ventilate your house through other means, such as opening windows just as you would with traditional central heating. 

Is an Air-to-Air Heat Pump right for me? 

Despite air-to-air heat pumps being extremely versatile, they’re not always right for every property. Most types will require an area outside your home where the outdoor unit can be mounted on a wall or installed on the ground. This unit will need space around it to get a good flow of air. Apartments and flats above ground floor may not have sufficient outdoor space for the outdoor unit although new systems are becoming available that do not require an external unit.

Other situations where air-to-air heat pumps will need a more complex installation include:

• Traditional properties with lots of small rooms and closed doors may require multiple indoor units.
• If you need domestic hot water, an air-to-air system alone won’t suffice, you’ll need a secondary solution such as an electric immersion heater or hot water cylinder.
• If planning restrictions apply (e.g. listed buildings or dense terraces), you must check outdoor-unit placement and noise rules. For multiple outdoor units planning permission may be required.

The success of your air-to-air heat pump will depend on your property layout, insulation, and the type of heating you’re replacing. They are best suited to homes or apartments that already rely on electric heating or storage heaters; have open-plan layouts where air can circulate freely between rooms and are modern and well-insulated. They can also be an excellent addition to your home offices, garden studios, or extensions where you want independent climate control. 

Air-to-air systems really excel in both heating and cooling spaces with good airflow. In a single, shared and large zone, such as a living/dining/kitchen area, for example, one indoor unit can heat the entire area efficiently.

Air-to-air heat pumps are becoming an increasingly attractive option for UK homeowners looking for an efficient way to heat and cool their homes. They offer lower running costs than many traditional electric heating systems, are relatively straightforward to install and can provide year-round comfort from a single system. As UK summers become warmer, the ability to cool your home is likely to become just as valuable as efficient winter heating.

However, they are not the right choice for every property. Before deciding, it's important to consider your home's layout, insulation, heating and hot water requirements, and whether an air-to-air or air-to-water heat pump would better suit your needs. A qualified installer can assess your property, explain the options available and recommend the most suitable system. When properly designed and installed, an air-to-air heat pump can provide reliable, low-carbon heating and cooling for many years to come.