Medium
7 23 on Ariston Clas ONE R

Your boiler has detected that the water temperature in one of your heating zones is higher than the system is designed to handle, so it has stopped that zone to prevent damage.

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

Zone 3 overheating

From this model's manual
Verified against the Ariston Clas One R installation & service manual, page 34.
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

7 21View →7 22View →

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