Low
S 30 on Ariston Genus 27

Your boiler has lost connection to the sensor that monitors the temperature outside, which may cause your heating to respond incorrectly to the weather.

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 open 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 31View →

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