Low
S 31 on Ariston Genus One 24

Your boiler is struggling to read the temperature from an outdoor sensor due to a loose wire or faulty connection, so it has reverted to a default setting.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

External sensor short circuit

From this model's manual
Verified against the Ariston/Ariston Genus One 24 installation & service manual.
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 30View →

All 26 fault codes on the Genus One 24

Seeing a different code? Every code this model can display, in one place.

A 02A01A03A07A17A18A33A97A99E 02E 06E 07E 08E 10E 20E 94E 95E 99S 01S 04S 05S 25S 26S 27S 80

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