BoilerFaultCodesYour boiler is performing a normal startup procedure by clearing out the combustion chamber before it begins heating your home.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Heatingmode:Advancefanoperation
What causes this fault?
This is a brief preparatory phase where the boiler's fan spins up to push air through the system and clear any leftover gases from the burner area. It is a necessary safety check to ensure the chamber is fresh and ready for a clean ignition. This is not a malfunction, but rather a standard step in the sequence before the heating starts.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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A boiler cover plan would cover faults like S.01 — no call-out fees, no surprises.
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