High Lockout
A11 on Vokera Condexa Pro

Your boiler is unable to start up safely because the fan that removes waste gases is not spinning correctly.

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

Fan error

What causes this fault?

This fault occurs when the boiler's internal computer detects that the fan is not spinning at the correct speed required to safely clear exhaust gases. The most common reason is a mechanical failure within the fan motor or a communication break in the wiring that tells the fan when to start. Without a functioning fan, the boiler will refuse to ignite as a vital safety precaution.

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 12View →

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