Air source heat pumps

Heat pumps are suitable for most homes and, depending on the system you are replacing, may reduce energy bills.

A heat pump is up to three times more efficient than a gas boiler. It works by capturing energy from outside (either in the air or ground) and moving it into your home. For every kW of electricity used by the heat pump, 2-4kW of heat is generated (compared to traditional gas boilers, which generate 0.9kW of heat per kW of gas). 

Heat pumps heat the water in your system to a lower temperature than a traditional gas boiler, so rather than switching it on and off when you require heat or hot water, it’s more efficient to keep it on continuously, consistently heating your home to your chosen temperature.   

A well-insulated home is best for a heat pump to work most efficiently, so a survey of your home should be carried out to see if insulation measures, e.g. loft or cavity wall insulation, are required before installation.

Changing your current heating system to a heat pump will decrease the carbon emissions your home generates due to its improved energy efficiency. The heat output is more than the electricity needed to power the pump. If you switch to a 100% renewable energy tariff,  the electricity used to power the pump will also be clean, reducing your carbon footprint even more.  

You can visit a heat pump that has already been installed near you, speak with the homeowners about their experience and get any queries you may have answered, for example, how much noise a heat pump makes – which is no more intrusive than a traditional gas boiler and, as it is located outside your home, should be barely noticeable.

Visit a heat pump near you.

Air source heat pump myth-busting

Heat pumps are a new, untested technology.

• This is not true. The technology used by air source heat pumps has been around for 160 years ( they use the same technology as your fridge ), so they are in no way a new, untested technology. They have been used in domestic homes since the 1960s, with improvements made to meet our current energy demands. 

Air-source heat pumps are not as efficient as gas boilers.

•  Air-source heat pumps are three times more energy efficient than the average gas boiler. Unlike typical boilers, which heat up and off throughout the day, a heat pump is designed to stay on in the background, maintaining a continuous temperature in your home. 

You need a well-insulated home for the heat pump to work.

• Yes, your home needs to be properly insulated first for a heat pump to be as efficient as possible. A survey can determine if additional insulation measures are required before installing a heat pump. Ensuring your property has sufficient insulation first will ensure that the heat generated by the heat pump stays in your home. 

Heat pumps aren’t right for the UK climate and can only work in warm countries. 

• That's not true. Heat pumps have been installed all over the world. They are particularly popular in Scandinavian countries, with 60% of homes in Norway having them. Air-source heat pumps work in temperatures as low as -25°C, and although they may use a little more energy during the coldest winter spells, they are still more energy efficient than a typical gas boiler. 

Heat pumps are noisy.

• With modern units this isn’t the case at all. The engine of the heat pump is called a compressor, and this generates a little bit of noise, ranging between 40-60 decibels (the same amount of noise as a refrigerator). With the heat pump being fitted outside the home, the noise levels should be no more intrusive than a gas boiler when you are indoors. 

Heat pumps are expensive to run.

• Like with most energy measures, it depends on your energy provider, what other energy efficient measures you have in your home and the energy system you are replacing. If your home is well insulated and you are using the heat pump efficiently, you should see a decrease in your energy bills. In fact, the more energy efficient measures you own or have in place, the better. This means you can connect everything together, saving you more money on your energy bills. 

Heat pumps need a lot of maintenance. 

• This is not true. Regular annual servicing is required, as is the case with gas boilers. However, as the pump has minimal moving parts, little maintenance should be necessary. 

Heat pumps take up too much space.

• A heat pump is kept outside your home and is about the same size as an adult bike. It only needs 1m at the front and each side to allow for ventilation. 

 If you would like more information about heat pumps, the Centre for Sustainable Energy go into detail on common questions and talk about the costs of heat pumps. 

Grants and projects are available across the county to help residents make significant energy-efficiency improvements to their properties. These include grants to fully fund such improvements for those in fuel poverty or on low income. If you would like more information regarding these projects and grants, contact us at retrofit@oxfordshire.gov.uk  or register your interest via our online form.