Low
d.15 on Vaillant ecoTEC Plus 630

This code is not an actual fault; it is simply showing you the current operating speed of your boiler's internal water pump.

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

Pump speed: Current value in %

Engineer required

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

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