Air Source Heat Pump FAQs

How do air source heat pumps work?

Heat pumps take energy from outside air which is used to heat a refrigerant and turn it into vapour. This gas is then squeezed and compressed, raising its temperature. This heat is released into your home, through your heating system.

Do air source heat pumps work in cold weather?

Heat pumps can work in temperatures as low as -20°C degrees, as they use 

the manipulation of refrigerants, making them suitable for most homes in the UK.

Do air source heat pumps work with radiators?

Heat pumps work with radiators and underfloor heating, but there may be instances where you need to replace your existing radiators if they are too small.

This is because the temperature of the flowing water in a building’s pipe network is higher when using a gas boiler, in comparison to an air source heat pump. 

This is often referred to as 'high flow temperature' and 'low flow temperature’. It is also one of the reasons heat pumps are much more efficient than gas boilers. 

In houses with gas boilers, radiators were installed to make sure the heat outputs were big enough to heat a room when the flow temperature was between 65 - 70°C. 

However, the flow temperature of an air source heat pump is significantly lower, at 40 - 50°C, meaning traditional radiators emit less heat . There may be instances where homes need larger radiators or fan coils to ensure they’re big enough to comfortably heat a room.

Are air source heat pumps noisy?

Similarly to gas boilers, heat pumps do make some noise, but due to Government regulations, most manufacturers run much quieter than their predecessors. A running heat pump will make a low whirring noise - this may increase if the pump is doing a lot of work, as the fan will be running at a higher speed. Many manufacturers have developed noiseless heating and cooling systems and tanks that work alongside the heat pumps, to ensure ultimate climate comfort.

Do you need planning permission for an air source heat pump?

Providing that the installation of an air source heat pump on a home meets the below criteria and aligns with your local planning authority, you do not need planning permission. According to Planning Portal, these permissions are:

• Development is permitted only if the air source heat pump installation complies with the Microgeneration Certification Scheme Planning Standards (MCS 020) or equivalent standards. Read more about the scheme.

• The volume of the air source heat pump’s outdoor compressor unit (including housing) must not exceed 0.6 cubic metres

• Only the first installation of an air source heat pump would be permitted development, and only if there is no existing wind turbine on a building or within the curtilage of that property. Additional wind turbines or air source heat pumps at the same property requires an application for planning permission

• All parts of the air source heat pump must be at least one metre from the property boundary

• Installations on pitched roofs are not permitted development. If installed on a flat roof all parts of the air source heat pump must be at least one metre from the external edge of that roof

• Permitted development rights do not apply for installations within the curtilage of a Listed Building or within a site designated as a Scheduled Monument

• On land within a Conservation Area or World Heritage Site the air source heat pump must not be installed on a wall or roof which fronts a highway or be nearer to any highway which bounds the property than any part of the building

• On land that is not within a Conservation Area or World Heritage Site, the air source heat pump must not be installed on a wall if that wall fronts a highway and any part of that wall is above the level of the ground storey.

In addition, the following conditions must also be met. The air source heat pump must be:

• Used solely for heating purposes

• Removed as soon as reasonably practicable when it is no longer needed for microgeneration

• Sited, so far as is practicable, to minimise its effect on the external appearance of the building and its effect on the amenity of the area.

How much electricity does an air source heat pump use?

Enula’s heat pumps are on average 400% efficient compared to gas boilers, with only 90% efficiency. 

This means on average for every kW of electricity you put in; you get 4kW of energy out.

Do air source heat pumps need servicing?

Heat pumps require very little maintenance. However, similarly to boilers they are recommended  to have a yearly service, and can last for up to 30 years.

Can you install an air source heat pump in an existing home?

Almost any home can be retrofitted with a heat pump, but there are some considerations to think about. For example, if your house is poorly insulated, this may need to be resolved prior to installation, so that heat doesn’t escape.

Do air source heat pumps work for air conditioning?

Heat pumps can be used to heat and cool homes, and can be used for air conditioning and heating units such as radiators and underfloor heating.

Can you install an air source heat pump in a flat?

Heat pumps can be installed in some flats. Thanks to modern, innovative designs, some heat pump manufacturers offer small heat pumps that sit on top of the tank, making flats compatible with air source heat pumps.

Can you install an air source heat pump in a flat?

Costs of Enula’s MSC approved heat pumps can be offset by a wide range of Government schemes, including the boiler replacement scheme. 

It’s important to remember that there are instances where you may need new radiators and heat emitters, or want underfloor heating which will increase the costs. 

If your house is on the grid, you can sell any renewable energy back to the grid (but you need a purchase agreement (PPA) in place).

How much does it cost to install an air source heat pump?

Costs of Enula’s air source heat pumps start from £8,000 but can exceed £15,000 depending on the nature of the project. These costs cover equipment and installation. There are however Government initiatives such as the Government’s boiler replacement scheme.

What size air source heat pump do you need?

The size of the heat pump you need is determined by the amount of energy the property uses and loses, and the size of the property. Units start from 3kW and go up to 20kW or larger for commercial type properties.

The installation of heat pumps on newbuild houses can often be much cheaper in comparison to a home renovation or retrofit that needs the old system removed in order to make room for the new system.

Can you link air source heat pumps to smart controls?

Enula have partnered with a range of industry leading brands including Panasonic, Samsung, Haier and Swegon who are at the forefront of offering smart renewable heating solutions. Their equipment can be controlled via an app or bluetooth, giving you the ability to monitor your heating wherever you are.