Emergency
E03 on Ferroli Maxima 35 S

Your boiler has detected that the flue gases are not being cleared away safely or the air intake is blocked, so it has shut itself down to prevent dangerous fumes from building up.

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

Fault code if they should occur (see page 27 troubleshooting)

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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