First unscrew the upper part of the fixing screw, then pry open the thermostat, and then rotate the right side of the repair cover. The specific operations are as follows:

1. First, use a screwdriver to pry out the red frame on the rubber screen, as shown in the picture below.

2. Then unscrew the internal fixing screws as shown in the picture.

3. As shown in the picture below, use a screwdriver to gently pry open the temperature adjustment knob along the red line.

4. Then remove the thermostat. There are two screws at the bottom. Tighten the screws and the repair cover will be removed.

5. As shown in the figure below, after removing the maintenance cover, the internal power supply structure of the water heater can return to normal.