Medium
B08 on Ariston Challenger 80E

Your boiler is having trouble communicating with its internal timer, which means your scheduled heating programs may not turn on or off as expected.

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

Time Clock

Engineer required

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

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B02View →

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