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FT series
Small fire tube steam boilers

FT series are compact fire tube steam generators available in different configurations, based on market demands and optimized for combination with any market burner.

Key features

steam capacity

Steam capacity

2 – 4 t/h



12 barg



up to 95%


NOx emissions

80 mg/Nm³
(lower values on request)


Simple and quick maintenance due to its two-pass design, with convenient access to the internal components of the boiler: furnace, inversion chamber, and tube plate.

Combustion system is suitable for different fuels: natural gas, biogas, GPL, hydrogen, diesel oil.

Small footprint and compact design.

High thermal efficiency due to efficient heat transfer, large exchange surfaces and optimized heat recovery systems (economizer).

FT boilers can be equipped with a multifunctional control system (OptiSpark or SMC) and dynamic monitoring of the boiler operation, ensuring optimal performance and safety even in offline mode.

Ability to fully integrate with Smart Factory complexes and other process control systems.

Low NOx emissions: less than 80 mg/m3 due to an optimized combination with any market burner (according to BAT).

Lower flue gas temperatures in the combustion chamber compared to reversed flame boilers.

Lower thermal stresses in the metal structure, increasing operating life.

More efficiency at partial loads.


The FT boiler is a fire tube steam generator, two-pass dry back type, with a horizontal design, fully packaged and complete with all the necessary control and safety devices. The two-pass design provides easy access to all internal parts, reducing downtime for inspection, maintenance and cleaning.

The heating surface and the fire tubes are designed to obtain high turbulence in the gaseous mass, ensuring high thermal efficiency. Thanks to the large furnace with ample diameter, combustion occurs with low NOx emissions (different to reversed flame boilers).

FT series steam generators are manufactured and certified according to the European Directive PED (other design codes and certifications can be applied including ASME, SELO, etc.).

FT steam boilers are supplied in standard and container versions.

Compatible products

Demineralization plant

Boiler water feeding requires low hardness concentration and conductivity to reduce the blow-down (heat loss). Two different types of treatment can be used: membrane-based technology and ionic-exchange solutions. Dedicated pre-treatments are necessary, based on the available water source.


It is necessary to remove CO2 and O2 to prevent corrosion phenomena. There are two options available: conventional packages composed of a tower and a drum, or the compact “smart” unit where the degassing equipment is realized inside the drum. The performance range is 7-20 ppb, according to the type of the installed unit.

Condensate treatment

It is necessary to purify the steam condensate from the process, to reduce water consumption and recover the heat contained in the condensate.

Dosing of chemical products

Oxygen scavengers are used as the protective dosage downstream of the thermo-physical degassers and the alkalizing agents to maintain a high pH inside the boiler. The choice of proper water treatment represents the energy optimization of the steam generator/water treatment package and a source of savings in water extraction and discharge costs.

FT Series Fire Tube

Technical Data

FT 100FT 200FT 300FT 400FT 500
Steam production [kg/h (up to)]10002000300040005000
Design pressure [barg]1212121212
Thermal efficiency [%]
according to EN12953, higher efficiency cn be reached with condensing systems on demand at defined boundary conditions
90* - 9590* - 9590* - 9590* - 9590* - 95
NOx emissions [mg/Nm3]
**lower emission levels on demand and depending on burner choice
80** - 15080** - 15080** - 15080** - 15080** - 150
Length [mm]39004500490055006100
Height [mm]19502300250026002800
Width [mm]18502000215022002300