Low
S.7 on Vaillant Atmomax

Your boiler is staying in a cooling-down phase for longer than expected after the heating has finished.

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

Heating mode – pump overrun error

DIY fix possible

Check that all radiator valves are fully open to allow water to circulateEnsure there is enough water pressure in the system (typically between 1.0 and 1.5 bar)Restart the boiler to see if the status clears

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Related fault codes

S.8View →F.27View →

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