High Lockout
e45 on Remeha Avanta Plus 35c

Your boiler's internal computer has suffered a software failure and can no longer process the settings needed to operate 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

Default parameters. Automation settings. Replace boiler control unit.

What causes this fault?

This fault occurs when the boiler's internal memory becomes corrupted and loses the essential factory settings required to run. The most common reason is an electrical surge or a terminal component failure on the control board that prevents the computer from reading its own software.

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

E43View →E44View →E11View →

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