BoilerFaultCodesYour boiler is not receiving enough electrical power from the mains supply 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: Under voltage
What causes this fault?
This fault occurs when the electrical voltage being supplied to the boiler drops below the minimum level required for the internal components to function. Typically, this is caused by a problem with the mains electricity coming into the property or a loose connection within the boiler's internal wiring. In some cases, it can also be triggered by a failing printed circuit board that can no longer process the incoming power correctly.
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 E385 — 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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