Medium
d.50 on Vaillant ecoTEC Plus 625

Your boiler is displaying a diagnostic setting for its internal air fan rather than a breakdown error, but it may indicate an issue with the fan's operation or the circuit board settings.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Correction of the minimum fan speed: 0 to 3000 rpm. Fan speed=Display value x 10

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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Related fault codes

F.32View →F.61View →F.62View →

All 170 fault codes on the ecoTEC Plus 625

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

cond.00D.000d.01d.02d.04d.05d.06d.07d.08d.09d.10d.11d.13d.14d.15d.16d.17d.18d.19d.20d.21d.22d.23d.24d.25d.27d.28d.31d.33d.34d.35d.36d.39d.40d.41d.43d.45d.47d.51d.58d.60d.61d.62d.64d.65d.66d.67d.68d.69d.70F.00F.0F.01F.1F.10F.11F.12F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.33F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.78F.83F.84F.85F.86F.87F.88F.89F.91F.92F.97F22F70P.00P.0P.01P.1P.02P.2P.3P.4P.5P.06P.6P.07S.0S.01S.1S.02S.2S.03S.3S.04S.4S.05S.5S.06S.6S.07S.7S.08S.8S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.33S.34S.36S.39S.41S.42S.46S.53S.54S.88S.91S.96S.97S.98S.99S.108S.109T.02T.03T.04T.05T.06T.08

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