Low
d.14 on Vaillant Home System

Your boiler is currently set to a specific speed for its internal pump rather than adjusting it automatically based on your home's needs.

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 mode of the modulating pump: 0=variable rotational speed (auto), 1;2;3;4;5=Fixed rotational speeds

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.00View →d.01View →d.15View →F.75View →

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