High
E 31 on Keston C40

Your boiler has stopped working because it is unable to accurately read the temperature of the water flowing through it due to a faulty sensor or loose wiring.

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

Flow thermistor short circuit - check/replace connections/thermistor

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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