High
F24 on Ferroli Optimax HE 31 C

Your boiler is struggling to clear exhaust gases because the fan component, which helps vent the system, is not receiving power or is failing to start.

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

Fan issues with wiring or power

From this model's manual
Verified against the Ferroli Optimax He 31 C installation & service manual.
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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