BoilerFaultCodesTechnical description
Flame not detected after 4 ignition attempts
What causes this fault?
This fault occurs when the boiler's internal computer doesn't see a flame after several attempts to light the gas. The most common reasons include a lack of gas reaching the unit, worn-out spark electrodes that can no longer create a flame, or a dirty sensor that fails to 'see' the heat even when it is present.
This fault is frequently seen during extreme cold snaps, as the external condensate pipe can freeze and back up, preventing the boiler from completing the ignition process.
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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