Use a multimeter to check the power of the heating ring and whether the thermocouple is damaged. If it needs to be replaced, please follow the following procedure:

1. Remove the hot half mold from the mold.

2. Remove the positioning ring (another function of the positioning ring is to fix the hot nozzle).

3. Install M3 screws on the lifting hole, remove the hot nozzle, and be careful not to pinch the heating ring.

4. Remove the snap ring and heat ring insulation cover.

5. Grasp the head of the hot nozzle, rotate clockwise and turn to pull the heating ring outward to gradually detach it from the hot nozzle.

6. When adding new wires to the device, the heating ring should be as close as possible to the main body of the hot nozzle, and the front end of the heating ring should reach the main groove of the front end of the inner core of the hot nozzle.

7. Rotate the heating ring clockwise to move it towards the head of the hot nozzle, ensuring that the heating wire completely reaches the front end of the hot nozzle. The distribution of the heating ring on the hot nozzle should be closer at both ends and more sparse at the center.

8. Install the heating ring insulation cover. If the insulation cover is tight, check if the heating ring is installed properly.

9. Install the circlip.

10. Detect the standard resistance value of the heating ring and calculate the power (the standard power is engraved on the heating ring), and detect the resistance value of the thermocouple (0 or smaller resistance).