BoilerFaultCodesTechnical description
Indicates a lockout fault; requires pressing the reset switch and waiting 15 seconds between attempts.
What causes this fault?
This fault happens when the boiler attempts to start up but fails to detect a steady flame, causing it to shut down for safety. It is usually caused by a lack of fuel reaching the burner or a component failing to generate the spark needed to ignite the gas. In some cases, the boiler may actually be lighting, but a faulty sensor is failing to tell the internal computer that the flame is present.
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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