Medium
2 01 on Ariston Clas One

Your boiler is struggling to detect the temperature of your hot water supply because a connection to one of its internal sensors has been lost.

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

D.H.W. storage 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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Related fault codes

2 02View →2 03View →

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