High Lockout
E02 on Keston C36

Your boiler thinks a flame has started when it shouldn't have, usually caused by an electrical glitch or a faulty sensor signal.

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

False flame - There is possibly a problem with the power supply.

What causes this fault?

This fault occurs when the boiler's control system detects a flame signal at a time when there shouldn't be a fire, such as during the startup checks. The most common reason is a sensor that has become damp or damaged and is sending a 'ghost' signal, or a fault within the main circuit board that is misreading electrical noise as a flame.

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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