BoilerFaultCodesWhat the manual says
Manufacturer manualAfter 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/Ferroli Sigma 40 Ff installation & service 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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All 10 fault codes on the Sigma 40 FF
Seeing a different code? Every code this model can display, in one place.