High
Red LED flashing on Potterton Prima 30B

Your boiler has stopped working because it failed to light the burner after three attempts, so it has locked itself 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.

What the manual says

Manufacturer manual

Lockout - press reset. Possible ignition failure after 3 attempts

From this model's manual
Verified against the Potterton Boiler Suprima 100 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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