
Meet the new, future-proofed Flow 8500
Brand new and BESA 2023 registered, the Flow 8500 will transform your heat network, carbon footprint, and customer comfort.
Designed for today’s energy landscape and to anticipate tomorrow’s changing needs, the Flow 8500 Indirect HIU is the future of energy efficient, community-centred heating.
Why specify the Flow 8500 Indirect HIU
BESA Registered
BESA 2023 regime test compliant, designed for energy efficient heat networks.
On Demand DHW
Improved domestic hot water response time while maintaining HIU efficiency.
Improved VWART
More energy efficiency due to improved VWART performance.

BESA registered
The Flow 8500 Indirect HIU has been developed by our in - house design team to meet BESA 2023 test regime and standards. Click on the links below to see our BESA 2023 results.
Next level improvements:
- BESA 2023 regime registered - The Flow 8500 has been rigorously tested to meet BESA 2023 test regime and standards.
- On demand Domestic Hot water – we’ve improved our keep warm function and it now has variable opening valves that adapt to the installation situation.
- New wet temperature sensors - enhances control performance that ensures consistent low return temperatures, especially under more demanding flow conditions.
- Improved plate heat exchanger - our high-performance plate heat exchangers are proven to meet Best Practice under the BESA Test Regime 2023 criteria.
- New precision temperature sensors ensure high performance and accurate control at very low flow rates.
- Smart software - new system software that allows for more flexibility over temperature settings and better predictive control.
