Hoval STU biomass boilers – perfecting combustion with EN+ wood pellets
The exceptionally high efficiencies and very low particulate emissions recently announced by Hoval for its STU biomass boilers are the result of thermally efficient design, advanced controls and high quality wood pellet fuel produced to the EN+ standard.
“Wood chips and some low quality wood pellets can vary considerably in their moisture content and dimensions and this has a direct impact on combustion efficiency,” explained Managing Director Adrian Walker. “For that reason we have optimised our STU boilers to run on wood pellets produced to the EN+ standard, thus achieving a close marriage between controls, hardware and fuel to get as close to complete combustion as possible.”
Independent testing of Hoval’s STU 195 wood pellet boiler by TÜV has confirmed efficiencies of up 92% with an average of just 3mg/MJ for particulate emissions. The Hoval STU achieves this through an intelligent combination of inverter controlled fuel feed augers and an extremely responsive induced air flow, regulated by a high quality, robust and strategically located lambda probe. Combustion is optimised by the Flametronix® PLC based touchscreen control system, which ensures the boiler matches demand with maximum efficiency.