Low
S.20 on Vaillant Combi Compact 242EB

Your boiler has received a request to provide hot water, but it is taking longer than expected to start the heating process.

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

Hot water requirement error

DIY fix possible

Check that your hot water taps are fully turned offTurn the boiler power off and back on again to reset the sequenceEnsure there is enough water pressure showing on the gauge (between 1.0 and 1.5 bar)

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Related fault codes

S.10View →S.14View →

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