The Vaillant ecoVIT VKK 256/5 condensing boiler is an indoor model designed exclusively for heating, with a power output of 24.3 kW and an integrated 100-liter tank that acts as a thermal flywheel. Its main feature is the total immersion of the burner and flue gas exchanger in technical water, a solution that guarantees stable and continuous heat distribution, with efficient operation even at low flow rates. Compact and quiet, thanks to well-designed insulation and a sturdy casing, this boiler is suitable for any type of system. It has a wide modulation range that allows for constant and balanced burner operation, improving efficiency and reducing waste. The primary exchanger is made of steel, and the boiler uses a pneumatic combustion system. It is also designed for conversion to propane. Its compact size and connections compatible with previous models make it easy to replace in existing systems.