High Lockout
A24 on Vokera Condexa Pro

Your boiler has stopped working because the fan that removes waste gases cannot spin at the correct speed.

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 required speed to safely clear exhaust fumes. The most common reasons are a buildup of dirt or debris inside the fan casing, a mechanical failure of the motor, or a communication issue between the circuit board and the fan.

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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