Low
d.1 on Vaillant Ecomax Condensing 600/800 series

Your boiler is currently running its internal pump to move leftover heat away from the system, which is a normal process and usually not a fault unless it stays on constantly.

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 over run

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.0View →F.22View →

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