High Lockout
28 on Glow-worm EnergySaver Combi

Your boiler has stopped working because the internal fan, which safely exhausts fumes, is not spinning correctly or communicating with the system.

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

The fan is stationary or there is no fan speed signal.

What causes this fault?

This fault occurs when the boiler's control system detects that the fan is either not spinning at all or is spinning at the wrong speed to safely expel exhaust gases. The most common reason is a mechanical failure within the fan motor itself, though a loose electrical connection or a fault on the main control board can also stop the fan from receiving power.

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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