How much does it cost to fix Ariston error code EE6666?

Typical repair cost for the Ariston EE6666 fault is £120-200 including labour.

EE6666 High

Ariston EE6666 Fault Code

Q: What does the Ariston EE6666 fault code mean?

Your boiler has stopped working because a sensor that measures the water temperature is sending an incorrect electrical signal, causing the system to shut down to prevent overheating.

The Ariston EE6666 fault code means: your boiler has stopped working because a sensor that measures the water temperature is sending an incorrect electrical signal, causing the system to shut down to prevent overheating.. It appears on 3 Ariston models in our database.

Technical description: Heating flow temperature probe short-circuited

Typical repair cost £120-200 (including labour)

Engineer required

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

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Ariston models that show the EE6666 fault code

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

Source

Ariston EE6666 fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.

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