Low
D.1 on Vaillant Combi Compact 242EB

Your boiler is currently cooling itself down after providing heating by keeping the pump running temporarily.

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

Water pump overrun – time for heat mode

DIY fix possible

Wait for several minutes as this is a normal part of the boiler's operationEnsure your radiator valves are open to help the heat dissipateCheck that your room thermostat is set to the desired temperature

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Related fault codes

D.0View →D.2View →

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