Corrosion Control by Sacrificial Anodes

The three basic corrosion control methods used in corrosion control of home appliances are (i) corrosion control by sacrificial anodes (ii) use of corrosion-resistant materials (iii) corrosion control by coatings and paint. 

The life of a hot water heater can be extended by checking and changing the deteriorating anode. The direct cost of not having to replace broken water heaters can 

The cost of replacing water heaters was estimated at 460 million/year, the cost of anode replacement was estimated at 780 million per year, and the cost of increased life expectancy of water heaters was estimated at 778 million/year. 

The benefits of anode maintenance are longer tank life, less rust buildup, and savings on costly changeovers. However, a cost-benefit analysis may show the cost of replacing anodes could exceed the cost of increased life expectancy or the cost of water heater replacement. Increased life expectancy without increased cost has not been shown to be technically feasible. It is also not known how much life is gained by the replacement of water heater anodes as the water heater can fail because of other reasons such as heating element failure. 

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