High
31 on Johnson Starley Comet 100

Your boiler has lost its connection with the internal temperature sensor that monitors the main heating output, meaning it can't tell how hot the water is.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Centra heating supply sensor error (open or short)

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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