BoilerFaultCodesTechnical description
Flame not detected due to a gas issue – the gas supply, power supply or igniter, electrode and lead need checking – contact a Gas Safe installer.
What causes this fault?
This fault occurs when the boiler tries to start up but fails to detect a steady flame after several attempts. The most common reasons are a temporary interruption in your gas supply, a build-up of carbon on the internal sensors, or a component failure like a worn-out ignition lead.
This fault is particularly common during freezing winter spells, as the external condensate pipe can freeze and back up, preventing the boiler from successfully 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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