How Air Source Heat Pumps Work: A Simple Guide

Chat to us on WhatsApp now

Air source heat pumps, or ASHPs, are heating systems that work by extracting heat from outside air and transferring it into your home. It runs on the refrigeration principle; the air runs through a compressor, increasing its temperature and throwing warm air out.

They produce lower carbon emissions compared to traditional boiler systems. Air source heat pumps are the perfect blend of energy- and money-saving.

“Highflow heating and plumbing ltd providing best plumbing and heating services”

Ready for a sustainable heating option? Speak with our trained professional about Air source heat pumps; call us at 01689 843 582 and 07958277695 or send us an email at, and we will get back to you as soon as possible.

“Let us delve into this comprehensive guide on how air source heat pumps work.”

Heat Pump Technology and How it Works

Air source heat pumps consist of two main components that are an outdoor unit and an indoor unit. The outdoor unit contains coils filled with refrigerant. Meanwhile, the indoor unit contains a compressor and heat exchange.

Here is how Air Source Heat Pumps works:

Step 1 – Absorbing heat

The process begins with the outdoor unit. The fan pulls outside air inside the unit and eventually across the refrigerant filled evaporator coils. Don’t worry if it’s cold outside; the refrigerant in these coils absorbs the thermal energy from the air.

Refrigerant has a very low boiling point, therefore allowing it to vaporise and absorb heat in cold conditions as well.

Step 2 – Compressing

Now, this gaseous refrigerant is compressed by a compressor that is already present in the unit. This compression increases the temperature and pressure of the refrigerant. As this is compressed, it turns into high pressure hot gas.

Step 3 – Heat Transfer to Indoor

In this step, the heat from the hot gas is transferred to cooler indoor air. This process mostly happened with the help of a heating exchange system. As the indoor air blows across the condenser’s coil, it heats up and is then circulated throughout the home or building.

During this process, the refrigerant loses heat and condenses into a liquid.

Step 4 – Recirculation

In this step, the cooled refrigerant liquid passes through an expansion valve, which reduces its pressure and makes it cool even more. Then, the refrigerant returns to outdoor evaporation coils to absorb heat from the outside air again to restart the cycle.

Step 5 – Reversal for Cooling

All the systems may not follow this step. In this, the systems that are equipped with a reversing valve or, in some machines, the heat pump can be used for cooling during warmer months. By reversing the flow of refrigerant, the indoor unit acts as an evaporator, absorbing heat from indoor air and expelling it outside through the outdoor unit.

In a nutshell, we can say:

Absorption of heat from outside ———> Compression and Heat Release ——–> Distribution of Heat

Benefits of Installing Air Source Heat Pumps

Installing air source heat pumps offers a lot of benefits, some of which are mentioned below:

  1. Energy Saving

    Air source heat pumps save electricity and energy as they use less electrical power than a standard heat energy appliance. Rather than generating heat, they simply move it from one place to another, which obviously requires less energy.

    This non-generative heating module can help you with saving the environment and money.

  2. Lower Carbon Emission

    Since Air source heat pumps run on electricity and not oil, coal or any other fossil fuel, their carbon footprint is very less than standard heating systems. The carbon emission will be lower or even zero if your electricity is sourced from renewable resources like the sun or wind. Air source heat pumps are perfect for eco-friendly homeowners.

  3. Versatility

    Air source heat pumps are not only built for heating but cooling as well. They are the perfect option for comfort around the year. This dual functionality and environmentally friendly nature make it perfect for all houses. This dual function also reduces the burden of buying and managing two appliances on the homeowner.

  4. Decreased Bills

    Although you may observe a high initial installation cost of Air source heat pumps, but the operational cost is cheaper than any standard heating system. This is because they have high efficiency and generally lower cost of electricity compared to gas or oil heaters.

    The consumption is also lower than your standard heating system, therefore saving you money on electricity and heating bills.

  5. Reliable

    Air source heat pumps can have a lifespan of up to 20 years or even more if properly cleaned and maintained in a timely manner. Since they have fewer mechanical components at risk of failure than combustion-based heating systems, which can lead to a lower maintenance cost over the time.

  6. Easy Installation

    Compared to ground source heat systems, Air source heat pumps are more accessible to install, and they do not require any land modification. This makes them best for urban and suburban settings where accessibility is limited.


Air source heat pumps are simple yet effective solutions for heating homes. This not only just saves your money but also saves the environment. They are efficient and eco-friendly; Air source heat pumps are making the way towards a green future.

About us

When it comes to the heating and plumbing within your property, you can depend on us. Here at Highflow Heating and Plumbing, we provide comprehensive solutions across an array of areas. We have a thorough knowledge of all kinds of systems and, with over 60 years of experience, can provide any advice, support, and care that is needed.

Call us on 01689 843 582 and we will solve all your doubts.

Got a question? Get in touch

Our team of plumbers and heating engineers are here to help, so don’t hold back. Whatever your query, get in touch. You can call us on 01689 843 582 or send us an email at