Medium
08 on Saunier Duval Isomax F30E

Your boiler's hot water storage tank sensor is failing to report the correct temperature, which might lead to inconsistent or no hot water.

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

Storage vessel thermistor/wiring fault

Engineer required

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

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