Medium
1p3 on Ariston Alteas One

Your boiler is struggling to circulate water properly, which is causing it to overheat and shut down temporarily for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

All Boilers

DIY fix possible

Check that your boiler pressure is between 1 and 1.5 bar on the display.Ensure all radiator valves are fully open to allow water to flow.Gently bleed your radiators to remove any trapped air pockets.

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Related fault codes

1P1View →1P2View →103View →104View →

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