Medium
F8 on Saunier Duval Themaclassic Plus F30E

Your boiler is having trouble detecting the temperature of the water stored for instant hot water, which may lead to inconsistent tap temperatures or the boiler struggling to start.

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

Micro-accumulation sensor fault

Engineer required

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

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Related fault codes

F1View →F2View →

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