High Lockout
Test3 on Vokera Pinnacle

Your boiler has identified an issue with the air fan, preventing it from safely clearing away exhaust gases and starting the ignition process.

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 fault

What causes this fault?

This fault occurs when the boiler's internal computer detects that the fan is not spinning at the correct speed or has failed to start entirely. The most common reason is mechanical wear and tear within the fan motor, though it can also be caused by a communication failure between the fan and the main control board.

This fault is slightly more frequent in winter, as the fan has to work harder and more consistently to meet higher heating demands, which can cause aging components to finally fail.

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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