What does a preignition check involve?

A preignition check is a critical phase in preparing a steam boiler for safe operation, focusing on ensuring that all systems are ready before combustion begins. One essential part of this process is verifying that the fuel pressure proving switch is closed. This switch plays a significant role in the safety of the fueling system; it ensures that the fuel system is adequately pressurized and that there is no leak or malfunction that could lead to unsafe conditions during ignition.

When the fuel pressure proving switch is closed, it indicates that the fuel system is functioning correctly and that the pressure is at an appropriate level for safe and efficient operation. This step is crucial to prevent potential ignition events in case there is inadequate fuel or a malfunction in the system.

In contrast, while checking electrical connections and testing burner flame intensity are important for overall equipment maintenance and operational efficiency, they do not specifically pertain to the preignition process as directly as verifying the status of the fuel pressure proving switch. Similarly, verifying fuel line temperature is relevant for operational efficiency but does not address the critical safety checks necessary immediately before ignition.