What is the difference between a standing pilot and an intermittent pilot system?

The distinction between a standing pilot and an intermittent pilot system lies primarily in their operation and efficiency. A standing pilot system features a small flame that continuously burns gas, providing a constant source of ignition for the burner when heat is required. This means that the standing pilot is always consuming fuel, which can lead to higher energy bills and is less efficient in terms of fuel usage.

In contrast, an intermittent pilot system is designed to illuminate only when heat is needed. It activates a spark or a flame only during the heating cycle, allowing for a reduction in gas consumption during idle periods. This on-demand approach not only optimizes energy use but also helps to lower operational costs, making it a more energy-efficient option in many cases.

Therefore, the emphasis of the correct answer on the operational characteristics of the two systems highlights their differences in how gas is utilized for ignition in heating appliances, emphasizing efficiency and fuel management as key factors.