High Lockout
A(6) on Potterton Flamingo RS40 RS50

Your boiler is unable to create the spark needed to light the gas because the ignition part or its wiring is faulty.

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

Electrode or lead damaged.

What causes this fault?

This fault occurs when the boiler's ignition system fails to generate the electrical arc needed to light the burner. It is usually caused by the metal electrode becoming worn and cracked over time, or the high-tension lead suffering from heat damage which prevents the spark from reaching the gas.

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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Related fault codes

A(1)View →A(4)View →

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