What you asked is a technical core question about electric kettle-thermostat. Whether the kettle can ensure that the water temperature reaches the boiling point mainly depends on whether the quality of the thermostat is guaranteed. At present, the imported thermostats are generally high-grade, that is to say, when the steam in the pot reaches a certain level, the temperature sensor will have a memory rebound and the switch will be turned off. But as soon as you open the lid, the steam will flow out, and the steam channel in the pot will not get enough steam, so the temperature sensor will not act. However, when the heating tube is always heated correctly, even if there is dry burning, the temperature sensor of the thermostat will have a memory rebound and automatically turn off the power supply, thus protecting the safety of electrical appliances and users.