Safety indicator (4) lights Emergency

Saunier Duval Safety indicator (4) lights Fault Code

Q: What does the Saunier Duval Safety indicator (4) lights fault code mean?

Your boiler has detected a safety issue and has shut itself down to prevent any potential danger.

Q: How much does it cost to fix Saunier Duval error code Safety indicator (4) lights?

Typical repair cost for the Saunier Duval Safety indicator (4) lights fault is £120-300 including labour.

Also written as SAFETYINDICATOR4LIGHTS — same fault.

The Saunier Duval Safety indicator (4) lights fault code means: your boiler has detected a safety issue and has shut itself down to prevent any potential danger.. It appears on 2 Saunier Duval models in our database.

Technical description: A malfunction or an abnormality gives rise to the disconnection of the appliance

Typical repair cost £120-300 (including labour)

Engineer required

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

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Saunier Duval models that show the Safety indicator (4) lights fault code

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

Source

Saunier Duval Safety indicator (4) lights fault code information on this page is sourced and cross-checked against the official Saunier Duval service / installation manuals for each affected model.

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