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.

What the manual says

Manufacturer manual

Low mains supply voltage. Electrical supply fault to property. Check incoming mains supply. Faulty wiring to appliance. Check wiring to appliance.

From this model's manual
Verified against the Johnson Starley C10d installation & service manual, page 28.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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