By 2035, the UK plans to stop installing new traditional boilers. Environmentally friendly heat pumps are becoming a popular alternative despite their initial high cost.
Already, about 250,000 homes in the UK use heat pumps. Thanks to programs like the Boiler Upgrade Scheme, which helps reduce the cost, more people can afford them.
This guide focuses on air-to-air heat pumps. It explains what they are, how to install them, their costs, available financial aid, and how to know if they are suitable for your home.
What Is An Air-to-Air Heat Pump?
Air-to-air heat pumps are similar to air conditioning units but have the added capability of generating heat.
These pumps are frequently seen in UK office buildings and are gaining popularity for home use.
Since they can cool homes, too, air-to-air heat pumps are already popular in many European countries. With the increasing occurrence of heatwaves in the UK due to climate change, more people in the UK will likely start using them.
How Does An Air-to-Air Heat Pump Work?
In the UK, most homes heat their rooms using radiators or underfloor heating, known as ‘wet’ heating systems. Air-to-air heat pumps offer the advantage of not needing such a system to warm the house.
These heat pumps distribute warm air through fan coil units (‘blowers’) or air ducting pipes. Blowers are often placed high on walls, saving space. Ducting systems, usually hidden inside ceiling voids, are more common in new houses as they are less visible.
Air-to-air heat pumps come in two types: single-head and multi-head.
Single-headed heat pump: A single-head system has one external unit and one blower inside the house. In contrast, a multi-head system uses one external unit with multiple blowers inside.
Single-head systems are usually sufficient in smaller UK homes or for heating a single room. A multi-head system or a ducted setup might be necessary for homes with more than two rooms.
Installation of blower-based systems can be quick and cost-effective, as there’s no need for a wet central heating system.
Multi-headed heat pump: For multi-head systems, pipes connect each blower to the external unit, as boilers connect to radiators. These pipes are typically hidden in slim plastic channels along the top edges of rooms to minimize visibility.
How To Install An Air-to-Air Heat Pump UK?
An air-to-air heat pump system includes an external unit, internal pipes, and individual ‘blowers’ set up in various rooms of your house.
First, a skilled technician will set up the external unit, choosing a location that minimizes the distance to the internal blowers.
They will adapt if your home has pipework compatible with the heat pump. New pipes might be installed if not, but this is rare as most homes already have adequate pipework.
Next, the technician will install blowers in the rooms you select. They will advise the optimal placement for these blowers, aiming to keep them as close to the existing pipework as possible.
This setup lets you heat your home using only warm air and electricity.
But How Will You Heat The Water?
Air-to-air heat pumps are not designed to heat water, so you’ll need a separate solution for your hot water needs, such as showers, baths, and kitchen taps. The best option will depend on your household’s hot water usage and space and budget constraints.
One possibility is to install a hot water cylinder with an electric immersion heater. Alternatively, you could opt for electric showers and localized water heaters, which heat water at the point of use.
These heaters can be powered by gas, LPG, or electricity. Gas-based heaters require a flue for ventilation, while electric heaters can be discreetly installed under the sink.
What Is The Cost Of An Air-to-Air Heat Pump?
The average cost of air-to-air heat pumps for a three-bedroom house ranges from £1,600 to £3,100. This is significantly cheaper than air source heat pumps, typically costing around £10,000. However, the Boiler Upgrade Scheme can reduce the cost of air source heat pumps by £7,500.
Installation of air-to-air heat pumps is also less expensive. This is because it only connects the external unit, which extracts the air, to the internal blowers that distribute the heat.
In contrast, air source heat pumps might require larger radiators if the existing ones are too small and new pipework to circulate the heated water, which adds to the installation costs.
Is My Home Suitable For An Air-to-Air Heat Pump?
These pumps are most effective in heating smaller homes. The efficiency of air-to-air heat pumps decreases as the size of the property increases, as they are better at quickly heating and maintaining warmth in smaller spaces. Larger rooms tend to lose heat more rapidly.
Since air-to-air heat pumps do not heat water, they cannot fully replace a boiler system. To heat water, you will need a different solution.
For homes looking to move away from gas boilers, one option is a hot water cylinder with an electric immersion heater, or you could choose a heat pump water heater.
However, remember that using an electric immersion heater generally costs more, especially when compared to gas-heated water.
Is There Any Alternative To An Air-to-Air Heat Pump In UK?
For larger homes transitioning from boilers, an air-source heat pump using air-to-water technology is a common choice. This type of pump can heat water and is well-suited for larger radiators and underfloor heating systems.
Another alternative is a ground source heat pump, which harnesses the natural warmth of the soil in your garden to heat your home. These heat pumps are known for their durability and longevity, making them an excellent eco-friendly replacement for traditional boilers.
However, they are the most expensive type of heat pump. The cost typically starts at £24,000 for a horizontal system and £49,000 for a vertical system.
Like air-source heat pumps, ground-source heat pumps are eligible for the Boiler Upgrade Scheme, allowing you to receive a £7,500 grant to assist with the expenses.
Final Thoughts
Air-to-air heat pumps are ideal for heating small, individual rooms, particularly if you already have a separate system for heating water.
However, if you need to invest in an additional water heating solution, the extra expense may not be justifiable for the average household or those with existing gas boilers seeking to lower their emissions.
An air or ground-source heat pump is generally a better choice for those with the budget. These systems offer more comprehensive heating solutions, including water heating, making them more suitable for a broader range of homes and needs.
Read more: Heat Pump Funds Guide | Air Source Grant Aid
