High
34 on Johnson Starley C16d

Your boiler is not receiving enough electrical power from your home's supply to operate safely.

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 supply voltage. Electrical supply fault to property or faulty wiring to appliance. Check incoming mains supply. Check wiring to appliance.

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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