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  • H2X Team

Introducing Heat Pumps

On 18 October 2021, the UK government unveiled its plan to provide 90,000 households with £5k grants to install new heat pumps¹. This is a critical step in the national target of installing over 600k heat pumps per year by 2028, and eventually phase out gas boilers to hit the UK’s 2050 net zero commitments.²


Although well established in European countries like Norway and Sweden, heat pumps are still viewed as a relatively new technology in the UK. As a result, they present significant design, installation and sizing challenges for heating engineers.


Here, we're going to take a deep dive into heat pumps. Examining what they are, the different types available and the benefits and challenges associated with their installation.




What is a heat pump?

Let’s start by answering the most basic question of all — what actually is a heat pump? In simple terms, it’s a system that moves, or pumps, heat from one place to another by using a compressor and circulating a structure of liquid or gas refrigerant. Through this process, heat is extracted from outside sources and pumped indoors.


While many believe heat pump technology is a recent innovation, this isn’t the case. It dates back to 1856, when Peter von Rittinger recognised the principle of the heat pump while conducting experiments on the use of water vapour’s latent heat for the evaporation of salt brine.³


Over 150 years later, the development of heat pump technology continues. Recent advances in compressor and controls technology have allowed the creation of systems that are much more efficient and easy to control.


Different types of heat pump

There are three types of heat pumps available for a built environment, and each is classified by where they source their primary energy. These three distinct types of heat pump are:

  • Air-source heat pumps

  • Ground-source heat pumps

  • Water-source heat pumps

Let’s take a look at each of these in a little more detail.


Air-source heat pumps

Usually mounted outside of a property, air-source heat pumps transfer heat from the outside air to water, heating rooms via radiators and underfloor heating. Heat from the air is absorbed into a fluid, which is passed through a heat exchanger into the pump, raising the temperature before transferring that heat to water.


Air-source heat pumps are the most common type of domestic heat pump, with installations across the UK already in their tens of thousands. This is largely because air-source heat pumps are:


  • Suitable for almost any type of property

  • Much easier and quicker to install than other types of heat pump currently available


Ground-source heat pumps

A ground-source heat pump works by transferring heat from the ground outside to heat a building's radiators or underfloor heating. Thermal transfer fluid, a mixture of water and antifreeze, flows around a loop of pipe buried outside.


Heat from the ground is then absorbed into the fluid, which then passes through a heat exchanger into the heat pump. This raises the temperature of the fluid and transfers heat to water.


Whilst ground-source heat pumps are typically more efficient than air-source heat pumps, they are more expensive and time-consuming to install, as they require significant excavation work in order to lay the necessary piping.


Water-source heat pumps

Water-source heat pumps work by extracting heat energy from any variety of water sources, which can include:

  • Lakes

  • Rivers

  • The sea

They use a series of submerged pipes containing a working fluid that absorbs the heat generated by the water. This is then turned into useful heat for space heating and hot water by compressing the working fluid so it can give the heat off at a much higher temperature.


Due to the fact that they need a considerable quantity of water in order to function effectively, water-source heat pumps are a more niche renewable technology, especially compared to air-source heat pumps.



learn about the successful installation of heat pumps in Lancashire

Read Grant Stores Case Study





Heat pump installation

There’s no doubt that heat pumps are a hot topic of discussion at the moment. This is mainly a direct result of UK government plans detailed above, but also because of increased public attention on reducing carbon emissions.


Given the attention heat pumps are currently attracting, it’s worth taking a closer look at the benefits and challenges associated with their installation


The benefits of heat pump installation

The UK government’s decision to make grants available for the installation of heat pumps in households across the country is an attempt to utilise some of the various benefits that heat pumps can provide.


Provided engineers are able to help facilitate their effective installation, heat pumps can provide customers with a host of advantages which include, but are not limited to:


  • Reduced carbon footprints: Heat pumps produce no carbon emissions unlike traditional gas and oil boilers. However, they do use electricity, so are not entirely carbon-free.

  • More efficient energy use: Heat pumps are highly efficient, so far less energy is used to produce heating and hot water, contributing to decreased energy bills.

  • Enhanced safety: Generally speaking, heat pumps are a much safer option than traditional heating systems based on combustion.

  • Reliability: With a lifespan of between 20 and 25 years, heat pumps are an incredibly reliable and long-term source of heat.

  • Multi-purpose usage: During warmer periods, heat pumps have the capacity to reverse their primary heating purpose and switch to cooling mode, thereby effectively acting as an air conditioner.

The challenges of heat pump installation

Despite the significant benefits that can come from the utilisation of heat pumps, it’s crucial to recognise there are installation challenges that heating engineers need to overcome before these can be recognised.


Poor or incorrect installation of a heat pump or its associated pipework is almost certain to impact overall efficiency and performance. So, let’s take a look at the two key challenges associated with heat pump installation:


  • Poor design: Nearly all problems associated with a heat pump system can be traced back to a poor initial design process. For example, if relevant and accurate heat loss calculations for a building haven’t been undertaken, or the heating distributing system hasn’t been calculated in detail, the system is unlikely to perform as expected.

  • Skill shortages: Heat pumps are still seen as a new and evolving technology for many engineers. As a result, there is a lack of knowledge and understanding around heat pump design and installation. Estimates suggest that, in the UK, there are currently only 3,000 trained heat pump engineers, a significant obstacle to the government's net zero plans.

Overcome challenges and start reaping the benefits

The benefits of heat pumps speak for themselves, and the technology looks set to contribute significantly towards more efficient energy usage. However, engineers will need to be able to overcome installation challenges to make this a reality.


As a result, it’s crucial that new and efficient processes are introduced so that engineers are able to:

  • Correctly design efficient systems

  • Increase productivity to plug the skills gap that threatens to derail the widespread installation of heat pumps.


In short, engineers need a solution that improves upon traditional design methods of sketching layouts and manually calculating results. Fortunately, software that can do all this and more is now becoming widely available.

Streamline heat pump design with H2X



Expand your technical and practical knowledge with our calculations guide. Start Producing Accurate Calculations




Streamline heat pump design with H2X

As we’ve discussed, comprehensive heat pump design processes are crucial to ensuring the successful installation of a heat pump system. An undersized heat pump will never meet the space heating and hot water demands of a property, and an oversized heat pump won’t generate heat efficiently.


Given these challenges, and a lack of skills, knowledge and expertise in the field of heat pump design and installation, heating engineers need a way to ensure quality and efficiency. That’s why H2X’s heating design software works to help you create flawless systems with significant quality improvements.


With our software, upload a PDF background for your design and use the intuitive user interface to draw the system layout.


By using our software to draw your system layout, you will receive:


  • Automated Calculations: Results are given for all of your system components such as pipe sizes, heat pump load, recirculation pump duty, and much more.

  • PDF Export: Export your system layout and results on a professional PDF set that comes with a cover sheet and title block with your logo.

  • Bill of Materials: Download an accurate bill of materials that includes all of the pipes, valves, fittings, and equipment that have been designed and calculated.


So, if you’re ready to start working more efficiently and improve the quality of your heat pump designs, book a demo of H2X today.


¹ What are heat pumps and why is the UK government pushing them?


² Plan to drive down the cost of clean heat


³ The History of Heat Pump Technology


Shortage of trained heat pump installers could set back net zero