High
356 on Worcester Bosch Junior 24i

Your boiler is not receiving a stable or strong enough supply of electricity to operate safely and has shut down as a result.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Low mains voltage – the voltage may be interrupted or inconsistent and needs checking

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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