High Lockout
E09 on Vokera Condexa Pro

Your boiler has shut down completely because an internal safety sensor has detected a critical fault that requires a professional inspection.

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 safety devices have been activated (lockout)

What causes this fault?

This fault occurs when the boiler's internal safety circuit is broken, triggering an immediate shutdown to protect the appliance from damage. The most common reason is a failure in the main control board or a triggered overheat sensor that prevents the system from operating safely. It can also be caused by loose internal wiring or a communication error between the boiler's electronic components.

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

E01View →E02View →E03View →

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