Medium
S 26 on Ariston Genus 30 Plus

Your boiler is struggling to accurately read the temperature of your hot water cylinder because there is an electrical fault with the sensor cable or the connection.

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

Tank sensor short circuit

From this model's manual
Verified against the Ariston Genus One 24 installation & service manual, page 45.
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

S 25View →S 27View →

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