Question

How does a flame rod or electrode function as a flame sensing device in a heating system, and what principle does it rely on for flame detection? What conditions are necessary for the electrical circuit involving the flame rod to be considered open or closed?

Answer 1

Flame rods or electrodes function as flame sensing devices in heating systems by detecting the presence or absence of a flame. They rely on the principle of ionized gases to detect the flame.

Step-by-step explanation:

Flame rods or electrodes function as flame sensing devices in heating systems by detecting the presence or absence of a flame. They rely on the principle of ionized gases to detect the flame. When a flame is present, ions are formed in the flame and conduct electricity. The flame rod or electrode is connected to an electrical circuit, and when the circuit is closed, it indicates the presence of a flame.

The electrical circuit involving the flame rod can be considered closed when there is a continuous flow of current through it. This occurs when the flame is present and ions are conducting electricity. On the other hand, the circuit is considered open when there is no flow of current, indicating the absence of a flame.