Medium
34 on Johnson Starley C16u

Your boiler is not receiving the correct amount of electricity from your home's power supply to operate safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Johnson Starley C16u installation & service manual, page 27.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if other appliances in your home are flickering or behaving strangelyEnsure the boiler's fused spur switch is fully turned on and the fuse hasn't partially blownContact your electricity network provider to see if there is a known power dip or 'brownout' in your area

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