Through industry practice, the currently popular boiler maintenance methods can generally be divided into two categories: "dry method" maintenance and "wet method" maintenance. Specific methods include desiccant method, drying method, nitrogen filling method, pressure maintenance method, alkaline solution method, ammonia water method, and ammonia-hydrazine method. Among these, the following methods are simple and practical, suitable for commonly used shell-type gas boilers, and can be referenced by enterprises for self-maintenance:

1. Desiccant Method

The desiccant method belongs to "dry method" maintenance and is suitable for the protection of boilers that will be out of service for an extended period (three months or longer).

1. When the boiler water temperature drops to 100–120°C, drain all the water from the boiler, and use the residual heat inside the boiler to dry the metal surfaces. Remove any scale and sludge deposits on the water side of the boiler.

2. Place the desiccant in suitable containers and distribute them in different locations within the boiler. Immediately close all steam and water valves to prevent external air from entering.

3. Commonly used desiccants include: anhydrous calcium chloride, quicklime, and silica gel. Desiccants have a moisture-absorbing effect, which helps keep metal surfaces dry and prevents corrosion.

4. It is important to note: After placing the desiccant, regularly inspect it. If the desiccant is found to be deliquesced, replace it immediately.

2. Drying Method

The drying method belongs to "dry method" maintenance and is often used for corrosion prevention during boiler maintenance. When the boiler water temperature drops to around 100°C, drain all the water from the boiler and use the residual heat to dry the metal surfaces of the boiler.