On a steam boiler, what is the function of the control named 'operator' during a pressure decrease?

When considering the function of the 'operator' control on a steam boiler during a pressure decrease, it is important to understand the role of various components in maintaining proper pressure levels within the system. In this case, the operator control is designed to respond to a drop in pressure by initiating the operation of the burner.

By starting the burner, the system compensates for the pressure loss, helping to restore the desired pressure in the boiler. Maintaining the correct pressure is crucial for the efficient operation of the steam system and for ensuring safety, as too low of a pressure can affect the performance and reliability of the boiler.

The other functions mentioned, such as stopping the burner, opening the safety valve, or closing the inlet valve, do not align with the primary objective of correcting a pressure decrease. Stopping the burner would exacerbate the pressure drop, while opening the safety valve is a measure meant to relieve excess pressure rather than respond to a decrease, and closing the inlet valve would restrict flow and potentially worsen the pressure situation. Thus, starting the burner is the appropriate response to counteract a decrease in steam boiler pressure.