BoilerFaultCodesTechnical description
Flame not detected.
What causes this fault?
This fault occurs when the boiler attempts to ignite several times but fails to detect a flame, causing the system to shut down for safety. The most common reasons include a lack of gas reaching the burner, worn-out spark electrodes, or a buildup of carbon on the sensor that 'sees' the flame.
This fault is frequently seen during extreme cold snaps, as the external condensate pipe can freeze and back up, preventing the boiler from lighting.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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