The RS/E and RS/EV series burners are characterised by a modular monoblock structure that means all necessary components can be combined in a single unit thus making installation easier, faster and, above all, more flexible. The burners cover a firing range from 1350 to 11100 kW, and they have been designed for use in hot water boilers or industrial steam generators. Operation can be “two stage progressive” or alternatively “modulating” with the installation of a PID logic regulator on the RS/E series burners while RS/EV series is fully “modulating”. The mechanisms of regulation allow to catch up a high modulation ratio on all firing rates range. The burner can, therefore, supply with precision the demanded power, guaranteeing an high efficiency system level and the stability setting, obtaining fuel consumption and operating costs reduction. The burner operation can be intermittent or continuous by menu setting. The innovative combustion head, adjustment system ensures perfect movement during modulation as well as reducing noise and pollutants.