If the pilot burner fails to ignite, what occurs after a short period of startup?

When the pilot burner fails to ignite during the startup of a system, it is critical for safety and operational reasons that the system has a mechanism in place to prevent further hazards. A lockout switch is designed to activate under such circumstances. This switch is a safety feature that helps ensure that the gas supply does not continue to flow unchecked, which could lead to dangerous conditions.

In most burner control systems, if the pilot light does not ignite after a predetermined period, the control system recognizes this failure and engages the lockout switch. This prevents further attempts at ignition and stops the flow of gas to avoid any potential accumulations that could lead to explosions or fires. The system typically will require manual resetting once the issue has been addressed to ensure safe operation moving forward.

The other options, while related to startup procedures, do not accurately describe the immediate actions taken by the system when a pilot burner fails to light. For example, a boiler shutting down may not occur immediately or in every scenario, and automatic resets usually only happen after successful ignition processes. Automatic cut-offs are usually part of the function of the lockout itself but may not represent the intention of the immediate response to an ignition failure.