High Lockout
432 on Baxi EcoBlue Heat

Your boiler has detected an issue with its electrical grounding system, which is a safety feature that prevents electrical faults.

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

Earth connector error

What causes this fault?

This fault occurs when the boiler's internal computer loses its physical connection to the electrical earth, which is a vital safety link. The most common reason is a loose or corroded wire within the boiler's internal harness, or a component failure on the main circuit board that prevents it from verifying the circuit is safe.

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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