BoilerFaultCodesWhat the manual says
Manufacturer manualSystem pressure has exceeded maximum pressure.
From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W B2kf Combi installation & service manual, page 82.
DIY fix possible
Locate a radiator in your home, preferably one upstairs.Using a radiator bleed key, slightly open the bleed valve to release a small amount of water into a container.Monitor the pressure gauge on the front of your boiler until it drops back into the green zone (typically between 1.0 and 1.5 bar).Close the valve tightly once the pressure is correct.
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Related fault codes
All 140 fault codes on the Vitodens 200-W B2KF Combi
Seeing a different code? Every code this model can display, in one place.
A.11A.12A.18A.20F.5F.7F.8F.9F.10F.11F.12F.13F.14F.15F.16F.29F.30F.49F.50F.57F.58F.59F.62F.63F.67F.68F.69F.70F.71F.72F.73F.74F.77F.89F.91F.92F.94F.100F.104F.142F.160F.161F.163F.182F.183F.184F.185F.299F.342F.345F.346F.348F.349F.350F.351F.352F.353F.354F.355F.357F.359F.361F.365F.366F.367F.369F.370F.372F.373F.377F.378F.379F.380F.381F.382F.383F.384F.385F.386F.387F.388F.395F.396F.399F.400F.401F.402F.403F.404F.405F.406F.408F.410F.416F.417F.418F.425F.430F.446F.447F.448F.449F.450F.451F.452F.453F.454F.455F.456F.457F.458F.462F.463F.464F.467F.468F.471F.473F.474F.517F.527F.528F.530F.540F.544F.545F.546F.547F.548F.549I.56I.57I.59P.1P.4P.8S.60S.74S.75