High Lockout
A09 on Vokera Condexa Pro

Your boiler's internal computer brain is having trouble processing information and has temporarily stopped working.

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

RAM error

What causes this fault?

This fault occurs when the boiler's main control board experiences a memory failure, preventing it from storing or reading vital operational data. It is typically caused by a hardware malfunction within the circuitry or an electrical surge that has corrupted the board's internal processors.

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

A 08View →A 16View →

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