High
2 5 on Saunier Duval Ecosy

Your boiler is shutting down because it senses the water is heating up far too quickly for it to be safe or normal.

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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