How much does it cost to fix Ferroli error code ER 9?

Typical repair cost for the Ferroli ER 9 fault is £150-250 including labour.

ER 9 High

Ferroli ER 9 Fault Code

Q: What does the Ferroli ER 9 fault code mean?

Your boiler has detected a communication error with its internal safety thermostat and has shut down to prevent the system from overheating.

Also written as ER9 — same fault.

The Ferroli ER 9 fault code means: your boiler has detected a communication error with its internal safety thermostat and has shut down to prevent the system from overheating.. It appears on 1 Ferroli model in our database.

Technical description: FAULT PROTECT SENSOR - Defective temperature limit sensor

Typical repair cost £150-250 (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 ER 9 fault code

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

Xignal Repair: £150-250

Source

Ferroli ER 9 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