BoilerFaultCodesYour boiler has detected an issue with its incoming electrical power supply, which is often caused by a voltage surge or a fault on the main circuit board.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main voltage error
What causes this fault?
This fault occurs when the boiler's internal computer detects that the incoming electricity supply is outside of the safe operating range. The most common reason is a power surge or a momentary spike in voltage that has affected the main circuit board's ability to monitor power safely. In some cases, it can also be triggered by loose internal wiring or a failing component that is drawing power incorrectly.
This fault is more common during autumn and winter storms, as lightning strikes or power grid fluctuations caused by high winds can trigger electrical surges.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E058 — no call-out fees, no surprises.
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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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