Medium
4 12 on Ariston E-Combi One 24

Your boiler has lost communication with the temperature sensor that controls your second heating zone, meaning it can't tell how warm that part of your home is.

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 2

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.

Engineer required

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

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Related fault codes

4 11View →4 13View →

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