High Lockout
09 on Vokera Easi-Heat 25

Your boiler has failed to fire up or complete its safety checks after several attempts and has now locked itself out for safety.

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

Final fault code (Refer to section 7.11)

What causes this fault?

This fault occurs when the boiler's control system fails to detect a flame after multiple ignition attempts, causing the unit to shut down for safety. The most common reasons are a lack of gas supply to the burner, a build-up of soot on the ignition sensors, or a failure in the electrical signals sent by the main control board.

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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