High
E43 on Remeha Avanta Plus 28c

Your boiler's internal computer has encountered a memory error and cannot safely process its settings, causing the system to shut down for safety.

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

Internal parameter error: SU (Safety Unit) memory error

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

E31View →E32View →E40View →

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