Technical Standard For UK HIU Test Regime

With over 50,000 Heat Interface Units (HIU)s being installed each year in the UK, setting performance standards has become increasingly important. This major update to the BESA Test Standard represents another step forward in improving HIU performance across the sector.

The UK Test Standard for Heat Interface Units is regarded as an important step towards improving the overall performance of existing and new build heat networks. The development of heat networks in the UK is a key component of the UK’s future energy strategy. The UK market for heat networks demands high efficiency in order to make it viable both financially and in carbon terms. A key component of a heat network is the HIU, which ensures heat is delivered efficiently to individual properties. Therefore, providing designers, specifiers and operators with impartial, accurate and useful information on the performance of HIUs, directly contributes to the success of the UK’s energy strategy.

In order to support the deployment of low-carbon heat networks, in 2015 the Department for Energy Security and Net Zero (DESNZ) provided funding designed to stimulate innovation that will help address cost and performance efficiency challenges related to heat networks. This included funding to develop a technical specification for an HIU testing standard that is appropriate for typical UK heat networks and to test a number of the market leading HIUs.

Following the conclusion of the project, BESA adopted the standard and a steering group of industry experts - The HIU Test Standard Group - has been established in order to develop the Test Standard and to provide a reference sounding board for sign-off on how to treat data in reporting.

This is the third version and includes major expansion, changes and updates. In particular, the standard has been restructured to a modular approach, to allow testing of additional types of HIU, with introduction of new test variants for those HIU types, including a Non-Keep Warm test, and new tests for space heating only HIUs. There has also been the introduction of a DHW load test and changes to the VWART calculation.

This version also introduces minimum standards which need to be met in order to
pass the Standard alongside reporting of whether Best Practice standards have been achieved.

It is clear that the scheme has already had a major impact on reducing carbon emissions and improving services in residential heat networks. But even more importantly it demonstrates the positive impact that consumer led initiatives can have on market development.

Also available to download are the individual BESA HIU Test Modules from 1 to 10.