High
2 5 on Saunier Duval Ecosy 24E

Your boiler is shutting down because the water inside is heating up much faster than the system can move it around, which suggests a blockage or a pump issue.

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 rate of temperature rise measured by the heating flow thermistor is too high.

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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