Low
S 30 on Ariston Genus Premium

Your boiler has lost signal from the temperature sensor located outside your home, meaning it doesn't know how hard it needs to work to match the outdoor 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

DIY fix possible

Check the external sensor on your outside wall for any obvious damage or loose wiresInspect the cable running from the sensor to the house for breaks or animal chewsReset the boiler to see if the communication error clears

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