Low
1 14 on Ariston Clas System 28

Your boiler is struggling to read the outdoor temperature, which means it may not adjust its heat levels automatically as the weather changes.

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 circuit open / short circuit

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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