What control device automatically shuts down the boiler at excess pressure?

The High Limit Pressuretrol is designed to monitor boiler pressure and automatically shut down the system if the pressure exceeds a predetermined limit. This is a crucial safety feature that helps prevent dangerous situations, such as equipment failure or catastrophic failures that could result in explosions or other serious hazards.

When the pressure within the boiler rises beyond the set limit, the High Limit Pressuretrol interrupts the power supply to the burner control, ensuring that the boiler does not continue to operate under unsafe conditions. This automatic response is vital for maintaining safe operating parameters and protecting both the boiler and surrounding equipment.

In contrast, a Safety Relief Valve serves a different function by providing a physical exit for excess steam or pressure, thus relieving the pressure but not actively shutting down the system. Other options, like the City-Water Make-up Actuator and the Draft Dampener Pressure Sensor, do not specifically monitor or control pressure in the same way that the High Limit Pressuretrol does. Therefore, recognizing the specific functionality of these different components is key to understanding how boiler systems are safeguarded against high-pressure scenarios.