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d.35 on Vaillant ecoTEC plus 612 VU GB 126/3-5

Your boiler is displaying an informational code intended for combination boilers, which usually does not affect this heating-only model.

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

Position of diverter valve (only 800 series)

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus Pro 839592 00 2004 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.

Engineer required

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

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Boiler cover options

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All 119 fault codes on the ecoTEC plus 612 VU GB 126/3-5

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

d.00d.01d.02d.03d.05d.06d.07d.08d.09d.10d.11d.17d.18d.19d.22d.23d.25d.26d.30d.33d.34d.36d.40d.41d.44d.47d.50d.51d.60d.61d.64d.65d.67d.68d.69d.70d.71d.72d.73d.75d.76d.77d.78d.80d.81d.82d.83d.84d.90d.91d.93d.97F.00F.01F.02F.10F.11F.13F.20F.22F.23F.24F.27F.28F.29F.32F.60F.61F.62F.63F.64F.65F.70F.71F.72F.73F.74F.75F.76P.1P.2P.3P.4P.5P.6S.00S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.36S.53S.54S.76

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