High Lockout
E11 on Remeha Avanta Plus 35c

Your boiler's computer brain has encountered an internal error and can no longer control the heating system 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

Internal control unit error

What causes this fault?

This fault occurs when the boiler's internal computer chips suffer a communication failure or hardware breakdown. The most common reason is electrical degradation of the components on the circuit board, which prevents it from processing safety data or commands correctly.

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

E10View →E12View →E32View →

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