High
neon flashing (Section I/M) on Potterton Performa 30 HE

Your boiler is failing to stay lit because it cannot properly detect the flame or is struggling to drain away waste water, causing it to 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

Flame sensing fault / Burner extinguishes after 10 seconds / Condensate drain blockage

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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