High
neon flashing (Section E) on Potterton Performa System HE

Your boiler has detected an issue with the airflow system, which means it cannot safely clear waste gases and has therefore shut itself down to prevent a hazard.

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

Air pressure switch proved - Check electrical and pressure tube connections, blockage of pressure tubes, restriction in flue or venturi.

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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