Medium
10 on Chaffoteaux Calydra 23 Green

Your boiler's hot water sensor has failed, meaning it cannot accurately measure or deliver hot water to 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

Domestic Hot Water thermistor faulty (short circuit)

Engineer required

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

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