How much does it cost to fix Ariston error code E29?

Typical repair cost for the Ariston E29 fault is £80-180 including labour.

E29 Medium

Ariston E29 Fault Code

Q: What does the Ariston E29 fault code mean?

Your boiler has lost its connection to the room thermostat or internal temperature sensor, meaning it doesn't know when to turn the heating on or off.

The Ariston E29 fault code means: your boiler has lost its connection to the room thermostat or internal temperature sensor, meaning it doesn't know when to turn the heating on or off.. It appears on 2 Ariston models in our database.

Technical description: Room sensor open circuit

Typical repair cost £80-180 (including labour)

DIY fix possible

Check if your room thermostat or programmer has run out of batteries and replace them if necessary.Ensure the thermostat is turned up higher than the current room temperature.Reset the boiler by turning the mode selector dial to 'Reset' for five seconds and then back to its original position.

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Ariston models that show the E29 fault code

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

Source

Ariston E29 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