What device responds to the temperature of the steam and closes when the steam warms the element?

The device that responds to the temperature of the steam and closes when the steam warms the element is a temperature sensor. A temperature sensor detects changes in temperature and can be integral in controlling systems that require activation or deactivation based on heat levels. For example, in a steam system, when the temperature of the steam rises, the temperature sensor can signal to shut off a valve or other mechanisms to prevent overheating or to maintain a specific temperature.

In steamfitting applications, properly understanding how temperature sensors function is critical to maintaining safe and efficient operation of heating systems. They play a crucial role in automation by providing feedback to the system, enabling it to adjust to varying conditions.

While air vents and flow control valves play important roles in steam systems, they do not specifically respond to temperature changes in the manner described. Pressure switches monitor pressure levels, which is a different parameter altogether. For effective temperature regulation in steam applications, temperature sensors are essential.