How much does it cost to fix Ferroli error code Boiler locks out?

Typical repair cost for the Ferroli Boiler locks out fault is £150-300 including labour.

Boiler locks out High

Ferroli Boiler locks out Fault Code

Q: What does the Ferroli Boiler locks out fault code mean?

Your boiler has detected a safety issue with overheating or power delivery and has shut itself down to prevent damage, meaning you currently have no heating or hot water.

Also written as BOILERLOCKSOUT — same fault.

The Ferroli Boiler locks out fault code means: your boiler has detected a safety issue with overheating or power delivery and has shut itself down to prevent damage, meaning you currently have no heating or hot water.. It appears on 1 Ferroli model in our database.

Technical description: Check 230 v on grey wire of terminal block x5 on main pcb; check for continuity through overheat thermostat

Typical repair cost £150-300 (including labour)

Engineer required

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

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Ferroli models that show the Boiler locks out fault code

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

Sigma 40 FF Repair: £150-300

Source

Ferroli Boiler locks out 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