Low
S 30 on Ariston Genus One 30

Your boiler is struggling to detect the temperature outside, so it is defaulting to a standard settings mode to ensure you still have heating and hot water.

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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