Flame sensing detectors in flame proven mode must have a self-checking feature.

• A. Yes
• B. No
• C. Sometimes
• D. Not specified

Answer: (A)

In flame proving systems, the ability to confirm that the flame detector itself is functioning is essential. The control relies on the detector to verify that a flame is actually present whenever fuel is supplied. If the detector could fail silently and the system kept fuel on, you’d have a dangerous condition. A self-checking feature continuously evaluates the detector and its electronics, ensuring the signal it provides is valid and timely. If any fault is detected, the system can shut down the fuel supply or raise a fault indication, rather than continuing to operate on potentially incorrect assumptions about flame presence. This safeguard keeps the burner in a safe, fail-safe state and is why this capability is required in flame proving mode.