High
Red light flashing on Potterton Prima 30B

Your boiler has failed to start the flame after three attempts and has locked itself 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

Lockout (indicated by the red light flashing). This occurs if the flame is not detected after three ignition attempts.

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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