Installing a heat pump: What you need to know

Things to consider before your heat pump installation

Heat pumps require an energy efficient home and a complementary heating system to get the best performance.

Before considering a heat pump it's important to have an engineer look at the below so they can advise on whether a heat pump is suitable for your home:

• Your hot water requirements
• The existing radiators and heating system

It may be necessary to upgrade your existing heating system to ensure that the heat pump will work efficiently; this could include:

• Increasing the size of your radiators and pipework
• Installation of underfloor heating
• Installation of a buffer tank (which keeps your water hot so it can be used later)
• Changing your hot water system (especially if you have a combi boiler)

How is a heat pump installed?

Generally speaking, whether you’re buying an air, ground or water source heat pump, you’ll find that they all follow the same 4 point installation process, which is:

1. Pre-installation process: Choose a well respected supplier who will check your home for the suitability of a heat pump.
2. Removal or update of your current heating system: The engineer will remove your old boiler, or modify whichever heating system you currently have.
3. The installation itself: Depending on which type of heat pump you’ve decided on, you'll have either both indoor and outdoor units, or just an outdoor unit installed. You can find more detailed information below.
4. Post-installation checks: At this stage, the installer checks that the heat pump is in full working order. From there, you can then keep on top of the maintenance of your system with a heat pump service plan.

The more technical side of the installation will depend on the type of system you have chosen.

How is an air source heat pump installed?

Your heat pump installation will depend on the model of heat pump you purchase. Some options may have an internal and external unit, while others may just have an external unit.

Also, if you don’t already have a cylinder to store hot water in your home, the engineer will fit this for you too.

Usually the inside unit will be mounted on a bracket on an outside facing wall so the engineer will need to drill a hole through the wall to feed cables and pipes outside, through the external unit.

You should keep in mind that this will not only mean that you don’t have any heating during the installation, but your home can get a bit colder while work is going on, so you may want to consider getting your heat pump installed in the warmer months.

The engineer will then connect the wires and pipes when installing the outside unit, which can be mounted to the outside wall of the building or secured to the ground.

On average this installation will take 2-5 days, depending on how complicated the installation is. The cost to install an air source heat pump can cost anywhere between £2,400 and £14,050.

How is a water source heat pump installed?

With a water source heat pump, the heat pump unit can either be installed on the inside or outside of your property.

Once this has been decided, the engineer will then run pipework from the heat pump unit to the edge of a nearby water source, which should be no more than 100 metres away from your property. These pipes will be buried in a trench around 0.5 metres deep and 40cm wide.

Once the pipes reach the waters edge, the engineer will connect them to a lake collector or pond mat, which consist of loops of pipes that are used to circulate a mixture of water and refrigerant. These collectors are then floated out on the surface of the water to a spot where they’ll be put in place by weights.

Like an air source heat pump, a water source heat pump can take 1-5 days to install - depending on the size of your property and how much preparation needs to be done. The cost to install a water source heat pump will usually be around £10,000.

How is a ground source heat pump installed?

The good thing about ground source heat pumps is that they can be installed virtually anywhere, as long as you have space to install the underground components.

However, they do take some planning and preparation. Of course, a ground source heat pump will need to be installed outside your property.

As well as reviewing your hot water requirements and existing heating system, it’s important that an engineer looks at the following before installing this type of heat pump:

• The level of insulation you have and;
• the geology and hydrology of the soil at your property.

Only after getting this information would your engineer know how to best fit your ground source heat pump. Once this has been established, your engineer can begin digging loop fields. This is put in place either horizontally or vertically so that the engineer can install the pipes, which will later be filled with a mixture of water and antifreeze that will act as a heat exchanger.

The engineer can change the way heat is distributed around your home. This can involve updating or adding underfloor heating or installing new ductwork, which transfers heat around the home through a series of vents in each room.

Once this work has been carried out, your engineer can then connect your heat pump to the new ductwork, the ground loop and the underfloor heating system.

How long does it take to install a heat pump?

This will completely depend on which heat pump you decide to have and how much work needs to be done at your home. In most cases the installation can take anything from 2 days to a couple weeks depending on your heat pump and your home.

How much does a heat pump installation cost?

Again, this will be decided on the type of heat pump that you choose and what work needs to be done in the installation process. You’’ll see on the table below that installation costs can get pricey, however with the Boiler Upgrade Scheme you can often get a grant which can help with the cost.

You can check if you’re eligible for this grant on the Government website.

How to choose the right heat pump installer

You’ll find that there’s a number of local or national heat pump installers out there. The best thing to do is look for the most highly rated and experienced companies to do this for. You can check reviews or speak to friends and family for recommendations.

Common questions about Installing a heat pump

Do I need planning permission to install a heat pump?

In the UK, you don’t need planning permission to install a heat pump. However, there are some conditions around listed buildings and World Heritage sites that you may need to consider. If you have any reservations then you should speak to your local authority.

Can I install my own heat pump?

Installing a heat pump without the correct qualifications and experience isn’t advisable. The installation process can be really technical, so you’re best to leave it to the professionals.

Looking for more on Heat Pumps?

If you’re looking for more information on heat pumps, then our Knowledge Hub is a great place to start. Here you can find a more in depth guide on how an air source heat pump works and advice on heat pump servicing.

For more information on energy saving tips, we have 12 great ways that you can save energy at home before you venture into the world of heat pumps.