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.

What the manual says

Manufacturer manual

Supply voltage under 190V. or over 250V.

From this model's manual
Verified against the Ferroli Maxima 35 S installation & service manual, page 29.
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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