Low
S.02 on Vaillant Combi Compact 242EB

Your boiler is currently preparing to provide heating and is checking that water is moving correctly through the system.

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 error – water pump running

DIY fix possible

Check that your room thermostat or programmer is set to 'On' and calling for heatEnsure the radiator valves are open to allow water to circulateWait 5-10 minutes as this code often simply indicates a normal pre-heating phase

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Related fault codes

S.00View →S.01View →S.03View →S.04View →

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