High Lockout
6 red flashes on Baxi EcoBlue Advance Heat

Your boiler has detected an internal communication or unexpected component fault and has stopped working as a safety precaution.

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

Miscellaneous error.

What causes this fault?

This fault occurs when the boiler's internal computer is unable to communicate with its electrical components or receives an unexpected signal that doesn't match normal operation. It is often caused by a malfunctioning main circuit board or a loose connection in the internal wiring harness that prevents instructions from being sent correctly. In some cases, a failing gas valve can also trigger this 'miscellaneous' error by sending unrecognised feedback to the control system.

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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