Water fuel HHO boilers series OH3000,OH5500,OH7500,OH10000 and OH20000 are designed for 1-20T boilers.We use HHO gas for industrial oil,gas or coal fired boilers to create enough combustion supporting on burner.The big comparison before and after using hho heating system is furnace burning fire complete combustion and black smoke reduction. Another unique feature is fuel saving 10-40% and then lower operation cost.If you are interested,inquiry us get the test report about fuel saving and operation cost after using HHO gas generators.