High Lockout
6 Red Flashes on Baxi MainEco

Your boiler has detected a general internal error, often linked to a small electronic glitch or a sensor that is failing to communicate correctly with the main controls.

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

What causes this fault?

This fault occurs when the boiler's internal computer receives conflicting information or loses contact with the main components that manage the heating process. It is typically caused by a communication breakdown between the electronic control board and the sensors, or small electrical fluctuations that disrupt the system's logic. In many cases, it indicates that the 'brain' of the boiler is no longer able to safely coordinate the startup sequence.

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

1 Red FlashView →4 Red FlashesView →

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