What type of ignition system remains active as long as the burner is operational?

The correct answer is intermittent ignition. This type of ignition system is designed to remain active only while the burner is in operation. In an intermittent ignition system, the ignition source is engaged to successfully start and then maintain the flame during operation, ensuring that the system can automatically reignite if the flame goes out during operation.

This system is more energy-efficient compared to other types because it doesn’t require a continuous ignition source; instead, it only operates when needed. Intermittent ignition is particularly relevant in modern burners, which often utilize electronic ignition methods that enhance safety and efficiency.

In contrast, the other options describe ignition systems that do not maintain an active ignition source throughout the entire burner operation. For example, interrupted ignition refers to systems that stop the ignition once the flame is established, while constant ignition presents an idea of never ceasing an ignition source, which is less common and typically less energy-efficient. Automated ignition systems refer more broadly to controls and may not specifically dictate the manner in which ignition is maintained during burner operation.