High Lockout
226 on Worcester Bosch GB162

Your boiler has entered a temporary lock-out mode because a service engineer's diagnostic tool was recently plugged in and has not been properly disconnected or reset.

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

Diagnosis tool was connected and is now locked out

What causes this fault?

This fault occurs when the boiler's internal computer remains in 'diagnostic mode' after being connected to a technician's service tool. It signifies that the communication between the boiler and the external hardware was interrupted or not closed down correctly, causing the system to stay frozen for safety. In most cases, it is simply a digital hang-up rather than a component failure.

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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