Low
D.19 on Vaillant Combi Compact 242EB

Your boiler is checking how the pump is running to move water around the system, which may cause temporary issues with heating performance.

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

Operating modes of the two speed heating pump

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

D.18View →

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