Medium
4 11 on Ariston E-Combi One 24

Your boiler has lost communication with the main thermostat or room 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 circuit open or short circuit ZONA 1

From this model's manual
Verified against the Ariston E Combi One 24 installation & service manual, page 38.
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 wireless thermostat has run out of batteries and replace them if necessary.Ensure the thermostat is within range of the boiler and has not been moved behind a metal object.Try resetting the boiler by pressing the 'Reset' button on the front panel.

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