Emergency
Burner air ports blocked on Ferroli Sigma 40 FF

Your boiler is struggling to breathe because the vents that pull in air for the flame have become clogged with debris or dust, preventing it from starting safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Clear air ports

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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