Get More Info The production program are combined hot water boilers for solid and liquid fuels. Combined heating boilers, low power TFF series are intended for open and closed heating systems mode, 90/70 ° C and the pressure to 2.5 bar. The firebox is made with water-cooled grate and customized using the domestic medium calorific coal granulation larger than 30mm, wood, cardboard, paper and the rest. The boiler is easy to handle, high quality and long lifetime. They are produced following types of boilers: TFF23, TFF32, TFF40, TFF 50 and TFF63, where the number in the name indicates the boiler in kW.