High Lockout
F2 on Glow-worm Xtramax HE

Your boiler has stopped working because the fan that removes waste gases is either spinning at the wrong speed or has stopped completely.

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: Fan speed incorrect or fan failed.

What causes this fault?

This fault occurs when the boiler's main control board detects that the internal fan is not rotating at the speed required to safely exhaust waste gases. The most common reason is a mechanical failure within the fan motor itself, though loose electrical connections or a fault on the main circuit board can also prevent the fan from starting.

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

F1View →F3View →

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