Beauty may take a long time, and there is scale on the heating plate. Before, my family had a brand-new intelligent teapot, which could control the cooking time and temperature. I consulted their customer service when I encountered this problem.

Because the power of the heating plate is very large, about kilowatt level, high power will produce high temperature. When the cold water is full, the scale gap of the heating plate is also full of cold water. Cold water is gasified at high temperature, but it is blocked by scale, so it can't release energy and steam quickly, resulting in cracking sound.

Solution: 1) Remove the scale on the heating plate manually with bamboo pieces and other objects, and do not damage it by force.

2) Heating an empty bottle and quickly pouring cold water to make the scale burst requires certain technology, which damages the heating plate and is misused by non-professionals.

Avoid: burn less mineral water (hard water) containing magnesium and other minerals and burn more pure water (soft water).

This is personal advice, you can try it.