Medium Lockout
S.06 on Glow-worm Flexicom cx

Your boiler is staying in a cooling-down mode because it thinks the internal fan needs to keep running to clear out heat or fumes.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

fan overrun

What causes this fault?

This fault occurs when the boiler's internal computer incorrectly thinks the system is too hot or that harmful gases haven't been fully cleared, causing the fan to run continuously. The most common reason is a communication error between the main circuit board and the fan, or a sensor that is failing to report that the boiler has safely cooled down.

DIY fix possible

Turn the boiler off at the fused spur switchWait for 30 secondsTurn the power back on and press the 'Reset' button

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Related fault codes

S.07View →S.08View →

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