Medium
30-80 (M, L, M, L, L, M) on Chaffoteaux Serelia 24 MFFI

Your boiler is struggling to detect the temperature of the water in your separate hot water cylinder, which may result in a lack of hot water at your taps.

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 cylinder bypassed

Engineer required

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

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