Medium
S.7 on Vaillant Combi Compact 242EB

Your boiler has finished its heating cycle but is struggling to circulate water to cool itself down correctly, which can cause the system to pause.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

Heating mode – pump overrun error

DIY fix possible

Ensure all radiator valves (TRVs) are fully open to allow water to circulateCheck that the boiler pressure gauge is between 1 and 1.5 barGently bleed air from the radiators if they feel cold at the top

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Related fault codes

S.8View →F.20View →

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