Low
d.34 on Vaillant ecoTEC plus aquaPLUS

Your boiler is checking the current speed of the internal fan to ensure it is venting exhaust gases correctly.

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 value of the rotary speed of the fan

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

No action is typically required as this is an information code rather than a permanent error.If the boiler is stuck on this screen, try pressing the 'Reset' button (flame icon).Ensure there are no obvious obstructions to the flue terminal on the outside of your property.

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Related fault codes

F.32View →d.33View →

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.05d.06d.08d.10d.11d.12d.13d.21d.22d.23d.24d.25d.30d.33d.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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