High
Boiler lockout on Ferroli Sigma 40 FF

Your boiler has stopped working because it cannot light the flame after several attempts, meaning you currently have no heating or hot water.

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

After a number of attempts at ignition, the electronic unit always shuts down the boiler. Check that the flue is clear and fitted correctly and that air has been vented from the pipes - polarity is correct. Check that the electrode is positioned correctly and free from corrosion deposits

From this model's manual
Verified against the Ferroli Sigma 40 Ff 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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