Time to unlock the potential in heat networks


13 March 2024



Collaborative industry-wide training will help to extend the deployment and improve the quality of heat networks across the UK, according to the Building Engineering Services Association (BESA).


The Association has received government funding to develop heat network engineering courses in partnership with the Manufacturers of Equipment for Heat Networks Association (MEHNA) and the Thermal Insulation Contractor’s Association (TICA).

The courses, which are now being delivered through BESA’s Training Academy1, are being made available at a key moment for the heat network industry. The Energy Act 2023 and the proposed Future Homes and Buildings Standards are expected to lead to a major expansion in the use of this technology.

New homes and commercial buildings will be able to comply with the Standards, which are due to come into force next year, if they are connected to heat networks that use low carbon technologies or reclaimed waste heat.

Just 2% of the country’s heat is currently distributed by networks, also known as district heating or district energy systems, but the government aims to grow that to 18% by 2050 in line with its net zero commitments. BESA also believes that networks could reduce heating costs in some cases by more than 30% – by recycling waste heat from factories, power stations and even the London Underground as well as CHP and biomass schemes.



However, some of the 14,000 systems already installed in the UK have suffered from technical issues and disappointing performance prompting the Department for Energy Security and Net Zero (DESNZ) to look for ways to raise design and installation standards.

This includes providing funding for the new training courses which allows BESA to offer 800 fully funded places on the introductory course, which is aimed at built environment professionals interested in growing their low carbon skills, and a further 100 on the installer course designed to upskill existing building services engineers.

The course content is aligned with the CIBSE code of practice (CP1) for heat networks and the sector’s developing technical standards. The programme includes a one-hour introductory foundation course and an installation and maintenance course comprising nine modules. The latter concludes with a practical session delivered by manufacturers Worcester Bosch and Baxi at one of four training centres in Dartford, Wakefield, Warrington and Worcester.

There are also plans for a quality assurance framework to improve reliability and guarantee levels of performance  all of which will increase demand for a larger workforce of well-trained heat network engineers.


“This is a great opportunity for anyone considering diversifying into heat networks,” said BESA’s director of training and skills Helen Yeulet. “This technology will play an increasingly important role in the transition to net zero, so it is vital that the country has enough trained installers who can help networks meet their full energy and cost-saving potential.”


Members of the three trade bodies who developed the course have already had early access to the training, but it is now being made available to the wider industry. And, ultimately, the organisations intend for the installer course to kickstart the development of a formal heat network qualification that will underpin future statutory regulation of the industry.

BESA has also recently updated and expanded its test regime for the Heat Interface Units (HIUs) which are used to distribute heat from networks to individual homes and commercial buildings.

Designed with consumer protection in mind and to ensure the market meets the needs of those developing and designing heat networks, the regime now offers improved information to specifiers to help deliver a better experience for end users.

The test regime is a voluntary process that gives manufacturers an independent method for testing, assessing, and comparing the performance of products.

It has already been successful in improving HIU performance across the sector by allowing specifiers to make more informed decisions about which HIUs to select.

HIUs extract heat from district heating networks to feed individual buildings and dwellings and the way they perform is central to the overall efficiency of the system. The BESA Standard originally emerged from an efficiency research project supported by the UK government to try and improve the performance of a technology seen as central to the decarbonisation of the country’s heating.

It has subsequently been developed and updated by the BESA HIU Steering Group, which is made up of representatives from all sides of the testing process. It engages with stakeholders right across the sector from developers, specifiers, and purchasers, through to manufacturers, installers/suppliers and ultimately, the customer.

Content continues after advertisements



This third edition of the HIU standard2 now takes a modular approach that allows for the testing of additional types of HIU

including space heating only models. It also introduces a DHW load test and an updated method for calculating annual volume weighted return temperature (VWART).

It covers seven different types of HIU and has pass/fail thresholds leading to registration of a successful test. The new modular nature of the tests is designed to minimise the amount of re-testing but maximises the information provided to specifiers.

Testing to the standard allows the performance of different HIUs to be evaluated in typical UK operating conditions and provides evidence of compliance with other performance and reliability metrics, such as domestic hot water response times.

“The original test standard has already had a significant positive impact on industry, but the new version represents a

major step forward as it raises professional standards and takes account of the shift to low carbon technologies,” said BESA HIU Steering Group chair Gareth Jones.

“The introduction of the new test standard is particularly timely given the impending introduction of a Heat Network Technical Assurance Scheme as part of upcoming heat network regulations. The shift to including hard pass thresholds fits well with these new requirements and will provide greater assurance to the market.

“Another great thing about the Standard is that it demonstrates the positive impact that consumer-led initiatives can have on market development,” added Jones, who is also managing director of Fairheat.

More than 50,000 HIUs are installed each year in the UK, and they are playing a growing part in the country’s overall decarbonisation strategy. This makes setting performance standards increasingly important.

“Ultimately, it will be consumers who benefit from the improved performance of heat networks as manufacturers use the test outputs to carry out more research and refine their products, and specifiers are helped to make increasingly better-informed choices,” said Jones.


For more information or to register your interest for either the Heat Network Foundation Course3 or the Heat Network Installation and Maintenance Course4 visit the website and enter the code: BESAHN23 to secure a fully funded training place.

More information about BESA HIU Standard can be downloaded at: www.thebesa.com/hiu/downloads


Info www.thebesa.com



  1. www.thebesa.com/besa-academy
  2. www.thebesa.com/hiu/test-registers
  3. www.thebesa.com/heat-networks-foundation-course
  4. www.thebesa.com/heat-networks-installation-maintenance-course