Medium
E29 on Ariston Egis 24 MFFI

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.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Room sensor open circuit

From this model's manual
Verified against the Ariston Bravo 24 Mffi installation & service manual, page 56.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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Related fault codes

E20View →E30View →

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