BoilerFaultCodesYour boiler is not receiving enough electrical power to run safely and has shut down to protect its internal components.
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 supply reaching the boiler's control centre drops below the minimum level required to operate the internal electronics. The most common reason is a malfunction within the main circuit board itself or a loose wiring connection that is preventing a steady flow of power. In some cases, it can also be triggered by a temporary drop in the mains electricity supply coming into your home.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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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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