How much does it cost to fix Ariston error code E64?

Typical repair cost for the Ariston E64 fault is £100-£180 including labour.

E64 High

Ariston E64 Fault Code

Q: What does the Ariston E64 fault code mean?

Your boiler has lost communication with the sensor that tracks the temperature of the water returning from your radiators, often resulting in the system shutting down for safety.

The Ariston E64 fault code means: your boiler has lost communication with the sensor that tracks the temperature of the water returning from your radiators, often resulting in the system shutting down for safety.. It appears on 3 Ariston models in our database.

Technical description: Heating return temperature probe in open circuit

Typical repair cost £100-£180 (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 E64 fault code

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

Source

Ariston E64 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