High Lockout
6 Green Flashes on Baxi MainEco

Your boiler is experiencing a communication error or internal electronic fault that is preventing it from running properly.

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, the Printed Circuit Board, loses the ability to send or receive messages from other components. It is often caused by a loose connection in the wiring or a hardware failure within the control board itself. Think of it like a computer crash where the system can no longer tell the boiler how to operate safely.

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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