High
neon flashing (3rd instance) on Potterton Performa 28i

Your boiler is struggling to confirm it is venting exhaust gases safely, causing the internal fan to run continuously at high speed to try and clear the system.

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

Fan runs at max speed. Air pressure switch proved. Go to section ‘D’.

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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