High
70°C neon flashing on Potterton Performa 24

Your boiler is failing to vent exhaust gases properly because it cannot confirm that the flue fan is working as it should, so it has shut down for safety.

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

Go to section ‘E’ - Air pressure switch proved fault.

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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