Low
S.27 on Vaillant Atmomax

Your boiler is temporarily running its internal pump to cool down the internal components after you have finished using hot water.

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

DHW mode – pump overrun

DIY fix possible

No action is required as this is a normal operational status rather than a fault.Wait a few minutes for the pump symbol to disappear.Ensure your radiator valves are open to allow heat to dissipate if the boiler is frequently running hot.

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Related fault codes

S.20View →S.28View →

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