Low
d.05 on Vaillant ecoTEC plus aquaPLUS

Your boiler is displaying the current temperature it is aiming for as it heats your water, which is a normal status message rather than a breakdown.

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

Flow temperature setting

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

Check if your heating or hot water is working as normalAdjust your thermostat or boiler temperature dial if you wish to change this settingMonitor the display to see if it changes to a different status code during operation

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Related fault codes

d.00View →d.01View →

All 106 fault codes on the ecoTEC plus aquaPLUS

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

d.00d.01d.02d.03d.04d.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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