8 yellow Emergency

Ferroli 8 yellow Fault Code

Also written as 8YELLOW — same fault.

The Ferroli 8 yellow fault code means: your boiler has detected that the gas valve is opening at the wrong time or when it hasn't been told to, which is a safety concern that prevents the appliance from running.. It appears on 1 Ferroli model in our database.

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: Gas valve (46) energised
Typical repair cost £180-350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Ferroli models that show the 8 yellow fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ferroli 8 yellow fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026