Low
d.01 on Vaillant ecoTEC plus aquaPLUS

Your boiler is continuing to circulate water after heating has finished to safely cool down the internal components.

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.

What the manual says

Manufacturer manual

Water pump over run

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus Aquaplus installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait for the timer to finish as this is normal operationCheck that your room thermostat is not set too highEnsure radiator valves are open to allow water flow

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Related fault codes

d.00View →d.02View →S.07View →

All 106 fault codes on the ecoTEC plus aquaPLUS

Seeing a different code? Every code this model can display, in one place.

d.00d.02d.03d.04d.05d.06d.08d.10d.11d.12d.13d.21d.22d.23d.24d.25d.30d.33d.34d.35d.37d.40d.41d.50d.60d.61d.64d.65d.67d.68d.69d.71d.72d.76d.79d.80d.81d.82d.83F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.27F.28F.29F.32F.33F.37F.41F.42F.43F.60F.61F.62F.63F.64F.65F.66F.67P.11P.12P.13S.00S.01S.02S.03S.4S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.33S.34S.36S.39S.53S.54

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