Quote:
Originally Posted by astra
It turns itself off after the water boiled up then cooled down to the required temp? I am bit confused.
|
No. The rheostat controls the water temperature, so when you start with cold water, the kettle heats the water to the limit of the rheostat setting. The water will never come to a complete boil (i.e. 212F) if the setting is below 212F/100C. The reason for using an external thermometer is because there is no temperature reading on the kettle, just marked positions for the rheostat.
So, for example, my rheostat is set below a full boil because I brew my coffee at 195F. You can hear water on the bottom of the kettle where the heating elements are as it simmers (boiling in tiny bubbles), but as the steam rises, it heats cooler water above and circulates the water apparently passing a sensor in the kettle that turns the kettle off when the sensor recognizes the rheostat setting.