High
F34 on Ferroli iBoiler 28

Your boiler is not receiving enough electrical power from the property's mains supply to operate safely and has shut down to protect its internal electronics.

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

Supply voltage under 170V – electric mains error

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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Related fault codes

F35View →F37View →A15View →

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