High Lockout
13 on Vokera Easi-Heat 25

Your boiler has detected an electrical communication problem within its internal wiring which is preventing it from running safely.

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

check the wiring harness

What causes this fault?

This fault occurs when the boiler's internal components lose the ability to speak to one another through the electrical wiring. It is usually caused by a loose connection, a damaged wire within the main harness, or a failing computer board that can no longer process signals. Because the boiler cannot confirm that all parts are working safely, it shuts down as a precaution.

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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