What is the purpose of a thermal fuse in an appliance?

A thermal fuse plays a crucial role in appliance safety by preventing overheating. It functions as a protective device that interrupts the electrical circuit if the temperature inside the appliance exceeds a predetermined threshold. This action is vital because excessive heat can lead to severe damage, including fires, and can compromise the safety and productivity of the appliance. Once the thermal fuse blows, it must be replaced in order to restore functionality to the appliance.

The other options do not accurately reflect the primary function of a thermal fuse. Regulating pressure, enhancing efficiency, or assisting in energy conversion does not relate to the safety-focused design of a thermal fuse, which is specifically intended to protect appliances from the risks associated with high temperatures.