Low
d.04 on Vaillant ecoTEC plus aquaPLUS

Your boiler is currently showing you the live temperature of the water inside your storage tank rather than an error code.

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

Actual tank temperature

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

Press the 'i' button to exit the diagnostic modeWait for the display to revert to the standard pressure or temperature viewIf the screen is stuck, briefly turn the boiler off and back on at the fused spur switch

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Related fault codes

d.00View →d.01View →d.02View →

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.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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