BoilerFaultCodesTechnical description
Flame not detected - check gas supply, ignition electrodes, and flame sensing
What causes this fault?
This fault occurs when the boiler's control system cannot confirm that a flame has successfully lit, leading it to shut down for safety. The most common reasons include a lack of gas reaching the burner, worn-out ignition components that fail to spark, or a dirty internal sensor that can no longer 'see' the flame.
This fault is significantly more common during extreme cold snaps, as the external condensate drainage 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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