High
1p2 on Ariston Alteas One

Your boiler is not circulating water correctly, meaning it is sensing that the temperature is rising too quickly and has stopped to prevent overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

All Boilers

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

1P1View →1P3View →103View →104View →

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