How Air Source Heat Pumps Work - Technical OverviewTypes of Heat Pumps & How They WorkDo Air Source Heat Pumps Work in Winter?Can Your Heat Pump Actually Freeze in Winter?Can Air Source Heat Pumps Cool Your Home in Summer?Will Air Source Heat Pumps Work in Older Homes?What is the Most Efficient Way to Run an Air Source Heat Pump?Pros and Cons of Heat PumpsWhat Funding Does the Government Offer for Heat Pumps?How Do Air Source Heat Pumps Work FAQs
How Air Source Heat Pumps Work - Technical OverviewTypes of Heat Pumps & How They WorkDo Air Source Heat Pumps Work in Winter?Can Your Heat Pump Actually Freeze in Winter?Can Air Source Heat Pumps Cool Your Home in Summer?Will Air Source Heat Pumps Work in Older Homes?What is the Most Efficient Way to Run an Air Source Heat Pump?Pros and Cons of Heat PumpsWhat Funding Does the Government Offer for Heat Pumps?How Do Air Source Heat Pumps Work FAQs
Air source heat pumps offer an innovative way to warm your home and are gaining traction in the UK. If you're still learning about heat pumps, you'll likely also wonder exactly how air source heat pumps work. Imagine a heating system that can pull warmth from the outside air. Air source heat pumps do exactly that. These clever systems take the heat that exists in the air (even when it's cold) and turn it into warmth for your home and water.
Still unsure about how air source heat pumps work? We've broken down the process into three simple steps to make it more clear for you:
1. Capture Outside Air: The heat pump pulls in outside air and extracts its hidden warmth using a special liquid called refrigerant.
2. Boost Temperature: The system compresses the refrigerant which dramatically increases its temperature using a small amount of electricity.
3. Distribute Heat: The heated refrigerant transfers its warmth into your home through radiators or underfloor heating which warms your living space.
Ready to upgrade your heating system? Get a free, no-obligation air source heat pump quote.
Your air source heat pump operates on a simple yet ingenious principle of heat transfer - making air source heat pumps worth it for efficient home heating and cooling. It uses a refrigerant that circulates through a closed loop system, absorbing heat from one area and releasing it in another. The main components of your heat pump include:
In heating mode, the refrigerant absorbs heat from the outside air (even in cold temperatures) as it evaporates in the outdoor coil. The compressor then pressurises this warm refrigerant vapour which raises its temperature further. As the hot refrigerant passes through the indoor coil, it releases heat into your home before being cooled and depressurised by the expansion valve, ready to start the cycle again.
In cooling mode, this process is simply reversed, with the indoor coil absorbing heat from your home and the outdoor coil releasing it outside.
Air source heat pumps are just one type of heat pump available for home heating. Here's an overview of the main types of heat pumps and how they work:
Ground source heat pumps utilise the stable temperature of the ground to extract heat. They circulate a fluid through buried pipes which absorbs heat from the ground. This heat is then transferred to the home using a heat exchanger.
Water source heat pumps draw heat from nearby bodies of water such as lakes or rivers. They operate by circulating a refrigerant through submerged pipes that absorb the water's heat. This extracted heat is then used to warm your home and provide hot water, leveraging the consistent temperature of the water source for efficiency.
As a recap, air source heat pumps work by extracting heat from the outside air, even in cooler temperatures. They use a refrigerant to absorb this heat which is then compressed to increase its temperature before being transferred to your home’s heating system. This process allows them to efficiently provide warmth and hot water throughout the year.
As mentioned above, even when it's cold, air source heat pumps can still extract heat from the outside air. These systems are designed to operate efficiently in temperatures as low as -15°C to -25°C, depending on the model.
In winter, your air source heat pump works by:
1. Extracting heat from the cold outside air.
2. Compressing this heat to raise its temperature.
3. Transferring the heated air into your home.
While the efficiency of a heat pump may decrease slightly in very cold weather, the best air source heat pumps are equipped with advanced technology to maintain performance. To ensure your air source heat pump works well in winter, you should:
Keep the outdoor unit clear of snow and ice.
Use appropriate temperature settings.
Ensure servicing has been done, if necessary.
💡 Top Tip: Proper sizing and installation of your air source heat pump is crucial for optimal winter performance.
Yes, your air source heat pump can freeze in winter, but it's not a cause for alarm. Modern air source heat pumps are designed with built-in defrost functions to handle this issue. These defrost cycles automatically activate when ice is detected, preventing a significant build-up that could impact efficiency and performance.
Also, many heat pumps have a heating element in the base that turns on when temperatures fall below a certain point to prevent internal freezing. While freezing can temporarily reduce efficiency, your heat pump should continue to operate effectively even in cold weather.
In short, yes, air source heat pumps can cool your home in summer. These versatile systems not only provide heating in winter but can also function as efficient cooling units during warmer months.
Here's how air source heat pumps cool your home in summer:
1. The heat pump reverses its normal heating process - it extracts heat from inside your home.
2. The indoor unit absorbs heat from the air inside your home, cooling the air as it passes over the refrigerant-filled coils.
3. The absorbed heat is then transferred to the outdoor unit, where it's released into the outside air, completing the cooling cycle.
The cooling efficiency of air source heat pumps is measured by the Energy Efficiency Ratio (EER). A higher EER indicates better cooling performance for the amount of electricity consumed.
It's important to note that while air-to-air heat pumps can provide both heating and cooling, air-to-water heat pumps typically only offer cooling through an active cooling process.
💡 Top Tip: If you struggle in the heat, understand that while an air source heat pump can cool, it may not be as powerful as a dedicated AC unit.
Yes, air source heat pumps can work effectively in older homes, but some considerations are necessary. Your older property may require certain improvements to maximise the heat pump's efficiency. You should start by getting a proper heat loss assessment to understand your home's thermal efficiency.
Improving insulation and draught-proofing is crucial to minimise heat loss and ensure optimal performance. While you may not need to replace all your radiators, some might need upgrading to accommodate the lower flow temperatures that heat pumps operate at. In some cases, you might need to add new radiators or consider underfloor heating.
Despite these challenges, with proper planning and adjustments, air source heat pumps can be a viable and efficient heating solution for your older home. If you're still unsure about your home's suitability, you can speak with a heat pump installer, such as Glow Green, for expert advice.
If you already have an air source heat pump or plan to get one in the near future, here's how to keep it running efficiently:
Keep the temperature stable: Set your heat pump to maintain a consistent temperature rather than frequently adjusting it. This allows the system to operate more efficiently and avoid energy-intensive temperature swings. Some users on Reddit advocate for a 'set it and forget it' approach which supports the idea of maintaining a consistent temperature (with adjustments for seasonal changes).
Clean or replace filters regularly: Clean or replace the air filters to prevent blockages and maintain proper airflow. This ensures the heat pump doesn't have to work harder than necessary.
Keep outdoor unit clear of obstructions: Remove any debris, leaves or snow from around the outdoor unit to allow for unrestricted airflow. This helps the heat pump extract heat more efficiently from the surrounding air.
Schedule annual professional maintenance: Have your heat pump serviced by a professional every few years to ensure it's operating at peak efficiency. They can check refrigerant levels, clean coils and identify any potential issues.
Use appropriate temperature settings: Set different temperatures for summer and winter to avoid unnecessary energy use. A comfortable winter setting might feel too cold in summer so it's important to adjust accordingly.
Ensure your home is well-insulated: Proper insulation in your walls, loft and floors minimises heat loss, allowing your heat pump to maintain a comfortable temperature with less energy consumption. Good insulation reduces the workload on your heat pump and increases its overall efficiency.
Seal air leaks: Air leaks around windows, doors and electrical outlets can undermine your home's energy efficiency. Seal these leaks with caulking, weatherstripping or tape to prevent warm air from escaping in the winter and cool air from escaping in the summer.
💡 Top Tip: Insulation, Insulation, Insulation! The key to unlocking your heat pump's efficiency starts with a well-insulated home.
If you're thinking about replacing your boiler with a heat pump, it's important to weigh the pros and cons to determine if it's the right choice for you.
Lower Carbon Footprint: Air source heat pumps produce significantly less carbon emissions compared to traditional heating systems which helps you reduce your environmental impact.
Energy Efficiency: Air source heat pumps are known for their high energy efficiency. They can produce more heat energy than the electrical energy they consume. This means you can potentially heat your home using less energy compared to traditional heating systems.
Versatility: Some air source heat pumps can provide both heating and cooling for your home.
Cost-Effective: While initial air source heat pumps costs are higher, you may save money on energy bills in the long run.
Space-Saving: Compared to ground source heat pumps, air source heat pumps require little space, with the main unit situated outside your property.
Higher Upfront Costs: The initial installation cost of an air source heat pump is typically higher than traditional heating systems.
Lower Heat Output: Heat pumps generally produce lower temperatures compared to oil or gas boilers so they may require larger radiators or underfloor heating for optimal performance.
Reduced Efficiency in Cold Weather: The performance of air source heat pumps can decrease when outdoor temperatures drop below a certain point.
Potential Noise: While modern units are designed to be quiet, some people may find the outdoor heat pump unit noisy, especially if poorly positioned.
Installation Considerations: Your property needs to be well-insulated for the system to work efficiently and you may need to make modifications to your existing heating system.
If you're seriously considering installing a heat pump in your home, you'll be pleased to know that the UK government offers significant financial support through air source heat pump grants. The primary initiative is the Boiler Upgrade Scheme which is available in England and Wales until March 2028. Under this scheme, you can receive a grant of £7,500 towards the cost of installing an air source heat pump. This grant, which was increased from £5,000 in October 2023, is part of the government's strategy to decarbonise home heating and achieve Net Zero by 2050.
Additional air source heat pump grants or incentives include:
ECO4 Scheme: This is a government energy efficiency scheme designed to target low-income and vulnerable households. The scheme aims to reduce energy bills and lower carbon emissions for eligible households by making their homes more energy-efficient.
0% VAT: A zero percent VAT rate is applied to the installation of both air source heat pumps and solar panels. This significantly reduces the overall cost of adopting renewable energy technologies for homeowners. The zero VAT rate applies to both the supply and installation of qualifying green energy systems.
Warmer Homes Scotland: This is a Scottish government scheme dedicated to supporting home energy improvements for eligible households. It offers grants and support for the installation of air source heat pumps, among other measures. The primary goal is to help low-income households improve their home's energy efficiency and reduce heating costs, making their homes warmer and more comfortable.
An air source heat pump is a device that extracts heat from the outside air and uses it to provide heating and hot water for your home.
Air source heat pumps are generally very efficient, often producing more heat energy than the electrical energy they consume.
The size of air source heat pump you'll need depends on various factors including your home's size, insulation levels and heating requirements. Reputable manufacturers like Daikin and Vaillant offer a range of air source heat pump sizes to suit different property types.
Air source heat pumps typically require less maintenance than traditional heating systems. However, regular checks and occasional professional servicing are recommended to ensure optimal performance.
It's not recommended to install an air source heat pump yourself. Professional installation is crucial to ensure the system works efficiently and safely.
