What happens in the ignition system when a successful ignition occurs?

When a successful ignition occurs in the ignition system, the primary result is that the main burner stays lit. This process involves the ignition system providing a spark that ignites the fuel-air mixture, allowing the main burner to function as intended. Once ignition is successful, the system transitions into its normal operating state where the burner remains lit and continues to produce heat.

This outcome is essential for the operation of gas appliances because maintaining a lit burner indicates that the combustion process is stable and efficient. By ensuring that the burner remains lit, the system can reliably provide heat without interruption, as long as the fuel supply and all other conditions are appropriate and safe.

The other choices typically describe processes or states that do not directly pertain to what happens immediately after ignition. For example, pressure equalization may occur in some systems but is not a direct result of ignition. Continuous sparking is not necessary once a flame is established, and filling the fuel tank completely does not relate to ignition outcomes—it pertains more to fuel storage rather than the ignition process itself.