What Are Heat Pumps & How Do They Work?

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How do heat pumps work?

Heat pumps are an energy-efficient way of heating water and a property in a sustainable way. These systems, which look much like an air conditioning unit, are designed to produce very little or no carbon emissions and could help reduce a person’s energy bills.

They work by taking the outside heat (thermal energy), either from the air, water or ground, and bring it inside via external pipes containing liquid, otherwise known as refrigerant. The fluid, which is similar to anti-freeze, will always be at a lower temperature than the thermal energy collected, so the heat collected transfers to the liquid in the pipes. This is similar to how a refrigerator works, but in the opposite way.

Although heat pumps use electricity to operate, the amount used is minimal compared to the amount of heat delivered to the property and they will cost less to run than a normal central heating system.

However, it is important to remember that the efficiency of heat pumps can rely heavily on how well insulated the property is. If there is poor insulation, the heat pump will have to work harder to heat a property – meaning the running costs will be higher. 

Can you install heat pumps in all properties?

When we see pictures of heat pumps, they are often shown as big boxes on the side of buildings, which can be unsightly or bulky. 

However, different types of heat pumps have been fitted in properties ranging from detached houses to apartments, including flats and even pre-war properties. You should certainly be able to find something that fits the requirements of the job you are on.
 

Which types of heat pumps are available?

Heat pumps collect thermal energy in three different ways: from the air, water or ground – moving the heat from one place to another, rather than generating new heat.

Below we will go through, in simple terms, each type of heat pump...

Do you need planning permission for a heat pump?

For most heat pump installations, it’s unlikely that you’ll need planning permission. Although, it’s still advisable to contact your local authority for advice and guidance before carrying out the work. 

It is also recommended that you check planning permission for heat pumps, as this could avoid any complications later on.

There are certain guidelines that can be referred to for heat pump installation, with key points such as:

• Air source heat pumps should be at least one metre from the boundary of the property.

• You cannot fit heat pumps to a pitched roof.

• Heat pump compressors and their housings must not be larger than 60 cubic centimetres.

• There are unique guidelines for property that is in an area of natural beauty or on protected land.

Are heat pumps noisy?

As with any heating system, it’s impossible to completely get rid of some noise while it’s working. The same is true of heat pumps. 

When there’s a lot of noise, this can be down to poor installation, but it’s fair to say that ground source heat pumps are a bit quieter than air source heat pumps. This is because of the consistent temperature from the ground itself, so the compressor doesn’t run at a higher power capacity. 

Air source heat pumps may run at a little more of an inconsistent level. That said, professional consultation and insulation of an air pump should limit noise levels, so they shouldn’t be too distracting. 

How much is a heat pump?

The cost of a heat pump can be anything from approximately £4,000 all the way up to £18,000 for the unit alone. However, the cost of these should fall as they become more mainstream. The final cost will really depend on a number of factors: the type of heating system you choose, how large the property is (which will dictate the size of the unit needed), along with the cost of installation by a professional installer. 

Is it cheaper to run a heat pump than a gas boiler?

Although the initial outlay of a heat pump is higher than that of a standard gas boiler, which works through a combustion system, the running costs should be considerably lower.

This is because the heat is drawn from either air or the ground on a heat pump, so is not as reliant on fuels. This is great in the long term, however the costs of installation can be high, which may mean it can take a while for a heat pump to pay for itself. 

That said, it can be an investment over time. Although heat pumps can require service, it’s less frequent than boiler maintenance, and even less expensive (depending on the issue).

Heat pumps vs gas boilers – what’s the other differences  between them?

A boiler can send heat to radiators quickly at high temperatures. Heat pumps give a more gradual increase in temperature, which means a slower climb in temperature. 

This is particularly effective in larger spaces, as the heating is steadier as it spreads throughout the room. 

Underfloor heating really benefits from this method, as it covers more space than individual radiators.

Are boilers being phased out?

There have been recent headlines about ‘banning’ boilers because of this inefficiency, and that might lead us to believe that we have to remove all existing boilers. This isn’t the case. 

From 2025, no new build properties will have gas boilers installed. Any home or commercial property built before this time may look to introduce a different method of heating over time. This can be a different, more energy-efficient boiler type, or an alternative method – like a heat pump.

We hope you have found this article useful, and if you need help planning your next heat pump installation, contact your local specialist Plumbing & Heating branch. where oOur experts are on hand to offer you help and advice.

With constant changes to the construction industry, we also understand that it can be challenging to keep track. That’s why we’re here with updates and advice within our Trade Corner hub, covering everything from site safety to home maintenance.

Disclaimer: The information contained on this page is intended as an overall introduction and is not intended as specific advice from a qualified professional. Travis Perkins aims to avoid, but accepts no liability, in the case that any information stated is out of date.

Always refer to the manufacturer's guidance for installation instructions and product maintenance.