SAV Systems has welcomed the announcement of a new regime for testing heat interface units (HIUs), noting its potential to significantly improve the performance of heat networks.

The company’s sales director Jan Hansen said: “Under-performance of heat networks is often down to poorly designed HIUs that are unable to cope with variations in the system and fail to maintain the temperature differentials required for optimum efficiency. This new testing regime is more demanding than its predecessor and the adoption of the new test standard by the Building Engineering Services Association will ensure wider compliance.”

SAV has supported HIU testing since the introduction of an earlier regime developed by Fairheat with support from the then Department of Energy & Climate Change (DECC). The first round of tests in the DECC funded project showed that SAV’s Danfoss FlatStation HIUs provided the lowest VWART (Volume Weighted Average Return Temperatures) values of all HIUs tested.

SAV will now be submitting FlatStations for testing under the new regime.

Mr Hansen added: “We are very focused on the performance of the whole system at both full and part load conditions and FlatStations are optimised to deal with varying system differential pressures and high performance at low, high and dynamic DHW tapping conditions.”

He continued: “We are therefore confident that they will exceed the requirements of the new tests. We are also particularly pleased the new regime will conduct tests based on both 70°C and 60°C primary supply temperatures as Danfoss FlatStations are optimised to perform efficiently with the low temperature heat networks of the future.”

“Indeed, we would like to see even more rigorous HIU testing, underpinned by penalties for heat networks that don’t perform adequately – such as failing to maintain a Delta T of 30°C. This will encourage a more holistic approach that looks beyond the HIUs to other factors such as correct installation and proper balancing of heat emitters,” he concluded.