High
F34 on Ferroli Maxima 35 S

Your boiler is experiencing electrical power issues because the electricity coming into your home is outside of the safe operating range for the unit's internal computer.

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 190V. or over 250V.

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

F37View →

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