BoilerFaultCodesYour boiler has detected an issue with the quality of the electricity coming into your home, meaning the power supply is not stable enough for it to operate safely.
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: Irregular mains frequency – electric supply problem
What causes this fault?
This fault occurs when the boiler's internal computer detects that the incoming electrical supply is fluctuating outside of the standard 50Hz frequency required in the UK. The most common reason is a temporary instability in the National Grid or a local power surge, though it can also be triggered by a degrading main control board failing to read the power correctly.
This fault may be more frequent during periods of extreme weather, such as heavy storms or lightning, which can cause temporary fluctuations and interference in the local electrical grid.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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