BoilerFaultCodesYour boiler has detected that the electricity supply coming from your home's mains or the local grid is too low for it to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Mains voltage too low
What causes this fault?
This fault occurs when the electrical supply entering the boiler drops below the minimum threshold required for the internal components to function. It is usually triggered by a temporary dip in the local power grid, though it can also be caused by loose internal wiring or a failing electronic control board within the unit.
This issue is more frequent during winter or periods of extreme weather when the local electrical grid is under heavy load or damaged by storms.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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