High Lockout
Neon2 on Ideal Classic FF 330

Your boiler is failing to start because the internal fan is not spinning correctly or the control board cannot confirm it is working.

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 voltage indication

What causes this fault?

This fault occurs when the boiler's control board sends power to the fan but does not receive the necessary electrical feedback to confirm it is spinning safely. The most common reasons are a seized fan motor due to age, a perished vacuum tube, or a failing computer board that can no longer process the fan's signal.

This fault is slightly more common in winter when the fan has to work harder to overcome heavy winds or when cold dampness affects aging electrical components.

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

Neon 1View →Neon 3View →

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