Medium Warning
S.06 on Glow-worm Ultracom sxi

Your boiler's fan is staying on for longer than it should after the heating has switched off.

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 detects that the fan is still spinning even though it has sent the command for it to stop. The most common reason is a communication error between the main circuit board and the fan, or a physical fault where the fan's motor is sticking in the 'on' position. In some cases, a faulty air pressure switch may be incorrectly telling the boiler that the fan is still active.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

S.32View →

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