Hot water boiler with three flue passes


Hot water generator with pressurised combustion and high energy efficiency, three flue gas passes.

Ready for operation in combination with a jet burner on liquid or gas fuel.

The arrangement and generous sizing of the combustion chamber with cooled end plate guarantee a low heating load and the possibility, when combined with a suitable burner, to ensure combustion with low NOx emissions.


Range consisting of 7 models with rated outputs from 6,000 to 15,000 kW.

  • Technical Data

    Boiler body made entirely from steel, completely lined with a layer of high-density mineral wool, protected by stainless steel plate, meaning very low heat loss to the surrounding environment.

    Energy efficiency exceeding 92%.

    Maximum operating pressure 6 bars, higher pressureon request.

    Maximum design temperature: 110°C.

    Combustion chamber consisting of a large furnace reinforced with omega joints to guarantee operation at low heating loads.

    Tube bundle on the second and third flue gas pass, with high heat exchange surface.

    Large inspection doors both on the front, for flue gas reversal from the second to third pass, and at the rear for the smokebox.

    Rear manhole for inspecting the furnace.

    Supplied in two parts, steel body complete with casing, and satellite controls.

    The water circuit can be inspected through a manhole at the top of the boiler and a hand opening ring at the bottom.

    Rear smokebox completely lined with high density mineral wool insulation.

    Thermostatic control panel. Thermostatic controller for single-stage or two-stage burners, with the possibility to control the system pump.




    • CE mark in accordance with the following directives
    • Gas Appliances (2016/426 GAR), for heat output ≤ 10 MW.
    • Pressure Equipment (2014/68/UE) for pressures greater  than 10 bars.




    THERMO EBM control panel. Electronic for managing the hot water generator (including with modulating burners), with microprocessor control; logical control unit housed inside the casing and user interface with LCD on the front panel.

    Outside probe. For boiler temperature compensation operation, to be connected to the THERMO EBM control panel.

    Cascade/outlet/storage cylinder probe. Connected to the THERMO EBM control panel based on requirements.

    Industrial control panel. For special needs regarding precision control or installation in safe environments.

    Control panel with PLC. For specific communication needs to BMS or supervision systems.

    Pipe stub for instrument connection. Able to house all the boiler control and safety instruments, available in different configurations.

    Stainless steel economiser to increase system efficiency by up to 5% (based on the system return temperature) by recovering heat from the flue gas.

    Economiser connection complete with return pipe extension, circulating pump with on-off valves and mechanical connection to the economiser performed directly at our facilities.

    Gas, oil or diesel burner.

    Perforated burner plate based on customer specifications.

    Ladder and walkway for safe access to the walkable platform on top of the boiler.

    Vertical flue connection.

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