High
Flow Switch on Potterton Promax FSB 30HE

Your boiler has detected that there is not enough water flowing through it, so it has safely shut itself down to prevent damage to its internal components.

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

Dry fire protection (No specific E-code in text)

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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