The EKO MAX LONG 100-400 boilers feature a horizontal tubular heat exchanger and are designed for burning pea-sized coal with a diameter of up to 30mm. The fuel feeding system is located at the back of the boiler and consists of a single screw fuel feeder. Additionally, it is protected against flame backflow with a flame extinction system using a BVTS valve connected to the water supply network. The burner is equipped with an independent primary and secondary air supply system. Air for the combustion process is supplied by separate blowers for primary and secondary air, and their operation is electronically controlled. These boilers offer the option to install an automatic pneumatic cleaning system for the tubular heat exchanger.