High
E40 on Remeha Avanta 28c

Your boiler has detected an internal fault within its heat recovery system, which means it has safely shut itself down to prevent potential damage.

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

HRU (Heat Recovery Unit) error: Internal check failed

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

E04View →E08View →

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