How Do Air Source Heat Pump Work UK?

Key takeaways:

  • Air source heat pumps are a highly efficient way to heat and cool your home, using renewable energy.
  • They work by transferring thermal energy from the air outside to a desired inside space, like a house or office building.
  • Some UK households can benefit from a free air source heat pump grant through the ECO4 Scheme.

If you’re looking for a long-term heating solution that will save you money in the long run and provide low emissions, air source heat pumps could be the perfect choice for you!

But what is an air source heat pump? And how do air source heat pumps work in the UK?

In this post, we’ll cover how an air source heat pump works, the key benefits of using this type of heating solution, and other topics including:

  • What is an air source heat pump?
  • How does an air source heat pump work?
  • Benefits of an air source heat pump
  • Does an air source heat pump suit your needs?
  • How much do air source heat pumps cost?
  • How much can you save on energy bills with an air source heat pump?

What is an air source heat pump?

An air source heat pump is a type of renewable energy system that uses the outside air to heat or cool your home. Air source heat pumps use electricity to transfer the existing heat from outside into your home, reducing the need for traditional heating and cooling systems.

These systems can gain heat from the air even when the temperature is as low as -15° C, helping home cut their energy costs throughout the cold winter months without compromising on the internal temperature.

There is an outdoor unit for every air source heat pump, which is mounted onto a wall or outside space, and an indoor unit which is connected to it. The indoor unit is where the warmth generated by the pump is distributed throughout your home.

How does an air source heat pump work?

1) Outside air is drawn into a network of tubes filled with a refrigerant.

2) The refrigerant absorbs the heat from the air and turns from a liquid to a gas.

3) The heated gas is then compressed, increasing its temperature further.

4) The hot gas passes through coils in the indoor unit, releasing heat into the home.

5) The refrigerant cools as it passes through the coils and returns to a liquid state, ready to start the process again.

The heat pump works like a refrigerator in reverse; it takes heat from outside and pumps it into your home. It is highly energy efficient as it does not create its own heat but rather transfers existing heat from one place to another.

Air source heat pumps also contain a reversing valve that allows the system to act as both a heating and cooling system, providing low-cost energy all year round.

There are two different air source heat pump types: Air-to-water heat pumps and Air-to-air heat pumps.

Air-to-water heat pumps

Most air source heat pumps use an air-to-water system.

Air-to-water systems work by transferring the heat energy from outside air, into a fluid which is then passed through a compressor and converted into usable heat.

This provides hot water for heating your home as well as providing hot water to showers, baths and taps. Air-to-water systems also have the added benefit of reducing your carbon footprint as they produce lower emissions than traditional boilers.

The heat from the air outside is absorbed at a low temperature into a fluid that’s passed through a compressor where its temperature is increased.

Air-to-air heat pumps

On the other hand, an air-to-air heat pump works by transferring the heat energy from outside air into an indoor unit which distributes warm air throughout your home using vents or radiators.

Commonly referred to as air conditioning, air-to-air systems are particularly suited for homes with a single source of heating, as they can be used to supplement existing boiler or fireplace systems.

It’s important to note, air-to-air heat pumps don’t provide hot water.

Benefits of an air source heat pump

There’s a lot to love about air source heat pumps, including:

  • High energy efficiency, helping reduce energy bills by up to 40%.
  • Their ability to work in low and high temperatures, meaning you can keep your home warm no matter the weather.
  • A strong lifespan of around 10 years, making them a much better long-term investment.
  • The fact that air source heat pumps are a cost-effective solution for heating and cooling your home all year round (including for underfloor heating).
  • Their ability to help you reduce your carbon footprint due to their lower carbon emissions.

Does an air source heat pump suit your needs?

Air source heat pumps are an efficient and cost-effective way to reduce your energy bills, help the environment and keep your home warm. They’re quickly becoming a popular option for many UK households, but there are some things you need to consider before deciding if an air source heat pump is right for you.

Is there somewhere to put the heat pump?

Air source heat pumps require an outdoor space to function, so you need to make sure there is enough space around the pump to allow a good flow of air.

There are two types of air source heat pump systems:

  • Monobloc system: These are a single outdoor unit containing both the compressor and expansion vessel, with pipes carrying water to the central heating system and hot water cylinder inside your property. Monobloc systems are an ideal solution for properties with limited space outside.
  • Split system: Air source heat pumps can also be split into two components, making them suitable for larger buildings. The outdoor component contains the compressor, while the inside component contains the expansion vessel.

How will the pump heat the rooms in your home?

Most UK households use radiators or a central heating system to circulate heat through their property, so you’ll need to make sure the air source heat pump is compatible with your existing set-up.

For homes that already have a central heating system, the existing pipework and radiators can be easily used in combination with an air-to-water air source heat pump system.

However, if you don’t want to install radiators or underfloor heating, perhaps an air-to-air system would better suit your needs as they require less plumbing and can be used as an additional heating system.

Does your property have a hot water cylinder?

A standard air-to-water air source heat pump requires a hot water cylinder, so you’ll need to check your property has one already installed.

If not, you can have one fitted or consider an alternative system. Typically, a hot water cylinder can be fitted inside any cupboard that measures around 80x80cm.

We’re aware some properties may not have space for a hot water cylinder. Luckily, there are alternatives available on the market.

Some hybrid heat pump systems are designed to work with a combination of boilers and hot water tanks, while others allow you to heat your home without the need for radiators. Air-to-air systems are another alternative as they don’t need a hot water cylinder.

Do you have the right insulation?

Air source heat pumps are most effective when the home they’re installed in is well-insulated.

As properties with single-glazed windows and poor insulation or in areas prone to extreme cold weather, you may find the heat generated is lost quite quickly through walls, windows and floors.

To learn how you could insulate your property for free, contact a member of the So Eco team today.

How much do air source heat pumps cost?

You may be asking, ‘How much are heat pumps?’

On average, air source heat pumps cost around £7,500 – £10,000 to install. Of course, the cost can vary depending on the size and type of system you choose.

However, it’s important to remember that while they may be more expensive upfront than alternative heating systems, such as oil boilers or LPG boilers, installing a heat pump could save you up to £1,500 a year in energy bills (but more on that in the next chapter)!

There’s also no denying that air source heat pumps are more energy efficient in the long run.

How much can you save on energy bills with an air source heat pump?

As mentioned in the last section, you could save up to £1,500 a year on your energy bills with an air source heat pump.

This is due to the fact that air source heat pumps are more efficient than traditional heating systems, especially old electric storage heaters. That’s not to mention the 2000 kg/year of CO2 you’ll be saving.

Properties with a G-rated oil boiler will slash their energy bills by £105/year in addition to reducing their CO2 output by a whopping 4300 kg/year! Additionally, homes with new electric storage heaters will save £890/year from installing a heat pump.

The only instances where installing an air source heat pump would lose you money would be if your home has a new A-rated gas or oil boiler. However, it’s hard to ignore their significant CO2 output (1800 kg/year for the gas boiler and 2900 kg/year for the oil boiler).

Are there air source heat pump grants?

Fortunately, yes, there are grants for heat pump installation.

Some UK households could benefit from a free air source heat pump through the Energy Company Obligation Scheme (ECO4). The scheme is funded by the UK government and aims to improve energy efficiency in low-income households.

To find out if you’re eligible for the ECO4 Scheme, contact a member of the So Eco team today.

Learn more: UK cost of living: 6 government grants helping the vulnerable & landlords

Slash your energy bills with So Eco

Thank you for reading our guide on air source heat pumps and how heat pumps work.

We hope you learnt something new!

At So Eco, we understand it can be difficult to know where to start when it comes to choosing the right heating system for your home. That’s why our team of experts are here to help.

From air source heat pumps and solar panels to loft insulation and internal walls insulation, So Eco offers a range of energy-efficient solutions tailored to your property and needs.

To find out more about how we could help you save money on energy bills, contact us today or check your eligibility with our online checker! We look forward to hearing from you.

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