BoilerFaultCodesYour boiler has failed to detect a flame, which means it cannot stay on safely and has stopped working for your protection.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Check the connection of the ionisation pin, use the pin to measure the ionisation current in series (this current should amount to at least 2 µAC).
What causes this fault?
This fault occurs when the boiler's control system cannot confirm that a flame has successfully lit, causing it to shut down for safety. The most common reasons are a worn-out sensor that can no longer 'see' the flame, a build-up of carbon on the probe, or a faulty internal component failing to send the ignition spark.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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