High
34 on Johnson Starley C10d

Your boiler is not receiving the correct amount of electricity from your home's power supply to run safely and has shut down as a precaution.

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. Check incoming mains supply. Faulty wiring to appliance. 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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