Low Information
S.05 on Glow-worm Ultracom sxi

Your boiler is continuing to run its internal fan or pump for a short period to safely cool down after the heating or hot water has been turned off.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

pump / fan overrun

What causes this fault?

This occurs when the boiler has finished heating your home and needs to dissipate residual heat from the internal components to prevent overheating. The system keeps the pump or fan running for a few minutes to circulate water or air until the temperature drops to a safe level. It is a standard safety feature of the appliance rather than a mechanical failure.

DIY fix possible

No action is required as this is a normal operational status message.Wait a few minutes for the boiler to complete its cooling cycle.If the code never disappears after 15 minutes, try resetting the boiler once.

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Related fault codes

S.04View →S.07View →S.08View →

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