BoilerFaultCodes.com
E29 High Lockout

Your boiler has detected an internal electrical connection problem that is preventing it from monitoring the system pressure correctly.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Fault in link on 6-way plug J11. Replace (pressure sensor) cable assy. Part No. 5107534

What causes this fault?

This fault occurs when the boiler's main control board loses its physical electrical link with the water pressure sensor. It is typically caused by a loose connection at the plug or a break in the internal wiring harness that monitors the system's safety levels. Because the boiler can no longer verify if there is enough water to operate safely, it will shut down as a precaution.

Typical repair cost £120-£200 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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