BoilerFaultCodesTechnical description
Unwanted flame formation.
What causes this fault?
This fault occurs when the boiler's sensors detect a flame signal even after the burner should have switched off. The most common reason is a carbon-coated or damaged ionisation probe sending a false signal, or a gas valve that is failing to close fully and allowing a small amount of fuel to leak through.
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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