What the manual says
Manufacturer manualNumber of blocks by the temperature sensor
From this model's manual
Verified against the Vaillant/Vaillant Ecofit Pure 412 installation & service manual, page 31.
DIY fix possible
Check that all radiator valves are fully openEnsure there is enough water pressure in the system (typically 1.0 to 1.5 bar)Bleed any air out of your radiators
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Related fault codes
All 129 fault codes on the ecoFIT Pure 418
Seeing a different code? Every code this model can display, in one place.
cond.00d.01d.02d.04d.05d.07d.08d.09d.10d.11d.13d.16d.17d.18d.20d.23d.24d.25d.27d.28d.31d.33d.34d.40d.41d.43d.45d.47d.50d.51d.58d.61d.62d.64d.65d.66d.67d.68d.69d.71d.75d.77d.80d.81d.82d.83d.84d.85d.90d.93d.94D.094d.95d.96D.096F.00F.01F.10F.11F.13F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.83F.85F.87F.88F.89P.00P.01P.02P.03P.06S.01S.02S.03S.04S.05S.06S.07S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109