BoilerFaultCodesYour boiler has detected an error while turning off the burner after you used your hot water taps, which may prevent it from firing up again.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Burner off after DHW demand (hot water - combi only)
What causes this fault?
This fault occurs when the boiler's internal computer detects that the burner flame is still present or being reported after you have finished using your hot water. It is usually caused by a communication error on the main circuit board or a mechanical part like the diverter valve failing to move into the correct position. In some cases, an external sensor may also be sending incorrect electrical signals that confuse the boiler's shutdown sequence.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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