High
Lockout (Rapid Flashing Red) on Potterton Ultra 2 30 DV

Your boiler has failed to start after three attempts, likely because it is struggling to find a stable gas supply or has air trapped in 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

The boiler will attempt to light, if the boiler does not light within 3 attempts (due to air in the system) the boiler controls will go to 'Lockout' and the upper Red LED on the control panel will go to a rapid flashing mode.

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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