Oxygen plays a central role in the corrosion of central heating systems, entering in the form of dissolved oxygen via tap water used for filling. As fire dies upon the removal of oxygen so the corrosion process also ceases. Corrosion Master significantly retards the corrosion process by raising the pH and restricting the amount of dissolved oxygen in the water. Once the dissolved oxygen has been eliminated the unit shuts down to be automatically reactivated upon the introduction of fresh oxygenated water. Additionally Zinc species that polarise existing corrosion cells are released into the water.