BG HHO TECHNOLOGY BOILER UPGRADES Brown’s Gas is a unique combustible gas generated from water that is comprised of hydrogen and oxygen intimately joined together in the exact ratio of two parts hydrogen to one part oxygen. When added to the air feed of a boiler’s furnace Brown’s Gas burns with the unburnt fossil fuel emissions which releases otherwise wasted heat potential, and gives the fossil fuel flame additional oxygen to more fully burn and so release more of its heat potential.