High
F34 on Ferroli Force W

Your boiler has detected that the electricity supply coming from your wall socket is too weak to operate the internal components safely.

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 180V.

From this model's manual
Verified against the Ferroli Force W installation & service manual, page 49.
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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Related fault codes

F35View →F37View →

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