Medium
D.14 on Vaillant Combi Compact 242EB

Your boiler is struggling to automatically adjust the water pump speed needed to circulate heat around your home.

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

Pump speed target value

Engineer required

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

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Related fault codes

F.75View →D.15View →

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