Medium
30 40 60 80 on Chaffoteaux Serelia 24 MFFI

Your boiler has detected a faulty reading from the sensor that manages your hot water temperature.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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

Thermistor sanitary bypassed.

Engineer required

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

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Related fault codes

30 40 60View →

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