High
Lockout on Potterton Puma 100e

Your boiler has stopped working because it couldn't successfully light the flame after three attempts, often caused by a temporary interruption in the gas supply or air in the lines.

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

Boiler fails to light within 3 attempts (due to air in the system). 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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