Medium
30 40 60 70 on Chaffoteaux Serelia 24 MFFI

Your boiler is struggling to detect the temperature of the water for your taps and showers, so it has turned off the hot water to prevent any issues.

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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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