Medium
50 70 on Chaffoteaux Serelia 24 MFFI

Your boiler is experiencing a communication error with its hot water temperature sensor, which is preventing it from providing hot water correctly.

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

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

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