High
36 on Saunier Duval Ecosy 24E

Your boiler has stopped working because it is unable to accurately measure the temperature of the water circulating through your radiators.

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

The heating flow thermistor is too resistant.

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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