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Last updated: 4 June 2024

Air Source Heat Pump Sizing: Which Size is Best for My Home?

Air source heat pump size
  • For an average 3-bedroom house, 5kW is the most suitable air source heat pump size.
  • Air source heat pump size is important because it directly affects how well your household’s energy needs are met.
  • The best air source heat pump size for a small house is 3kW, while the best size for a large house is 16kW.

An air source heat pump in the UK can be a great addition to your home if you are looking to reduce your energy bills and your carbon footprint. If you are ready to install this technology for your home, one of the first things you need to consider is air source heat pump size. 

In what follows, we walk you through what air source heat pump sizing means to determine which kind of appliance would be the best fit for you. However, if you find yourself left with more questions than answers about heat pump sizes, the best thing to do is consult an air source heat pump installer. 

Unfortunately, finding a professional you can trust can be easier said than done. After hours of tedious research, you might still end up empty-handed. To avoid any frustration, let us help you get your search for the right installer started in just 30 seconds

Simply fill in our short form and we will have up to 4 local air source heat pump installers from our network of reputable specialists reach out to you with free, non-binding quotes for their services. This way, you can easily find the installer that meets all your requirements. 

On top of that, by comparing heat pump quotes in the UK, you will also be able to secure the best deal for your new air source heat pump installation. Simply click below to start your search for the right installer today! 

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How big are air source heat pumps?

Air source heat pump size vs dimension

When you are asking yourself: “What size air source heat pump do I need?” you are referring to the power output of an air source heat pump. This is measured in kilowatts (kW) and indicates how much energy the heat pump will be able to generate for your home. 

It is important to note that air source heat pump sizing directly affects the heat pump cost you can expect to pay. The higher the power output of the appliance, the higher the total cost of the air source heat pump installation

On the other hand, if you want to know how big an air source heat pump is, then you are referring to the dimensions of the appliance. While dimensions vary per manufacturer, air source heat pumps are around 100-150 centimetres high and 50-100 centimetres wide

This means that air source heat pumps are compact units that won’t take up too much space. Nevertheless, you will need to make sure that you have enough room to accommodate an air source heat pump installation for your home.

How to calculate the heat pump size you need

Before installing an air to air heat pump or an air to water heat pump, you will need to find out which air source heat pump size is right for you. In the UK, the most common domestic air source heat pump sizes are between 4kW and 16kW. However, smaller or larger sizes are also available, if needed. 

There are a few factors you will need to consider when trying to calculate the heat pump size you need. Primarily, you will need to take into account your household’s energy consumption requirements

You will also need to factor in your home’s insulation, as a well-insulated home will need a smaller air source heat pump size than a poorly-insulated one. If your home is not adequately insulated, it’s strongly advised that you make some improvements to your insulation before installing a heat pump.

Below you can find an air source heat pump sizing calculator we have devised to help you determine what kind of heat pump you’d need based on the size of your home and your energy needs. The sizes we have listed are for well-insulated homes. 

Average Air Source Heat Pump Size Per Household Size
Size of the HomeEstimated Annual Energy DemandEstimated Required Air Source Heat Pump Size
1 bedroom8,000 kWh3kW
2-3 bedrooms12,000 kWh4-5kW
4 bedrooms17,000 kWh10kW
5+ bedrooms21,000 kWh16kW

Still not sure what heat pump size would be the best fit for your home? Then, you will want to bring any questions and concerns to an installer who specialises in heat pumps. Yet, finding an installer you can trust can be a tedious process. Thankfully, you don’t have to go through it alone. 

Instead of wasting hours researching local installers, let us put you in touch with up to 4 air source heat pump installers vetted by us. Just fill in our 30-second form and wait for the installers to reach out to you with free, no-obligation quotes for an air source heat pump installation. Then, simply compare prices to find a great deal and decide which installer you would trust to offer you the best tailored advice when it comes to heat pump sizing. Click below to get started now! 

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Why does the size of my air source heat pump matter?

Air source heat pump size per home size

Air source heat pump size is important because it determines how well your household’s energy consumption needs can be met. Ensuring that you have the best air source heat pump size for your home is the best way to avoid overspending on your yearly energy expenses while enjoying all the benefits that come with renewable energy systems. 

However, the wrong air source heat pump size can have detrimental effects on your energy consumption, as well as on your bank account. For instance, if you install an air source heat pump with a higher power output than what you actually require, you will be paying more for your heat pump. At the same time, if the size of your heat pump is too large, the resources it uses to operate are wasted, leading to higher expenses on your part. 

On the other hand, if your air source heat pump is too small, the appliance can be overworked when trying to keep up with your energy needs. As a result, it can deteriorate rapidly, leaving you without an efficient energy system and having to spend lots of money to replace it. 

So, the importance of taking the time to calculate heat pump size cannot be overstated. By finding the right air source heat pump size, you can ensure that your household can enjoy optimal energy consumption without having to overpay for it. 

What size air source heat pump is the best for my home?

Which air source heat pump is the right choice

As we have explained, an air source heat pump will be the right size for you if it can tend to your energy needs. Factors such as the size of your home and your specific energy consumption requirements directly determine the air source heat pump size you will need. 

There are two things you can do to ensure that you are not overspending on your new air source heat pump. The first is checking whether you are eligible for a heat pump grant that can lessen the financial burden of installing renewable energy systems for your home. The other is finding the installer with the best deal for a new air source heat pump installation. 

To make this process as hassle-free as possible, let us help you get in touch with up to 4 reputable professionals in no time. Rather than spending hours or even days of your precious time researching installers in your area, simply fill in our 30-second form. Then, just wait for the specialists we’ve vetted to reach out to you with free, non-binding quotes for an air source heat pump installation. This way, you can secure the best deal and choose the installer you trust to help you find the best heat pump size for your home. Just click below to get started now!

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  • Payment by finance available
  • Save £7,500 with BUS grant
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It only takes 30 seconds

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