Strategies to prevent scale attempt to keep the components of scale such as calcium and magnesium suspended in the boiler water or to reduce their concentrations in the boiler water. Corrosion is reduced by adding oxygen scavenging chemicals to the boiler water. Boiler water testing is required to ensure that conditions suitable for scale and corrosion are not present. Scale build up is usually not a problem in hot water boilers. Although make up water contains dissolved minerals, system leaks discharge water with an equal amount of dissolved minerals.
Corrosion remains a problem so oxygen scavenging chemicals are added to address the problem.