High
E36 on Keston System S40

Your boiler has stopped working because a sensor that monitors the temperature of the water leaving the unit has failed or become disconnected.

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 open 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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Related fault codes

E31View →E32View →E37View →

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