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

Your boiler has lost the ability to detect the temperature of the water used for your taps and shower, so it has stopped providing hot water to ensure safety.

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 open

Engineer required

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

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