What is the function of a thermostat in an appliance?

The function of a thermostat in an appliance is to regulate temperature by controlling the heating element. This is essential in various appliances, such as ovens, refrigerators, and heating systems, where maintaining a precise temperature is critical for proper operation and safety.

When the thermostat detects that the temperature has fallen below or risen above a predetermined set point, it sends a signal to the heating element (like a burner or heating coil) to turn on or off. This feedback loop helps to ensure that the internal temperature of the appliance stays within the desired range, leading to efficient operation and preventing overheating or overcooling.

The other options do not accurately describe the primary role of a thermostat. While initiating the power supply and displaying the temperature are important functions in some appliances, they are not the main purpose of a thermostat. Additionally, filtering impurities in the air relates to air quality systems, not temperature regulation.