Low
d.01 on Vaillant ecoTEC Plus 938

Your boiler is simply performing a routine safety cycle to circulate leftover warm water after the heating has switched off, which is a normal part of its operation.

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 overrun in heating mode: 1 to 60 min. Default: 5

Engineer required

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

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