Low
S 31 on Ariston Genus One 30

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.

Technical description

External sensor short circuit

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 →

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