The quality of the storage water heater liner directly affects the safety, health and service life of the water heater. QB/T 2590-2021 "Enamel Units of Storage Water Heaters" was issued, causing a high degree of attention to the enterprise, with a valuable impact on the water heater industry, which benefit to regulate the quality of water heaters enamel units. In order to meet the needs of industry development and further understanding of the standard, this paper compared the changes in technical content before and after the revision of the standard. The revision of the standard basically solves the problems identified in the current storage water heater enamel units industry.