Low
S.74 on Viessmann Vitodens 200-W B2KF Combi

Your boiler is currently focused on heating your hot water, so it has temporarily paused the central heating for your radiators.

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

Heating suppression; heating DHW circulation pump active

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W B2kf Combi 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

Check if a hot water tap has been left running slightlyWait up to 20 minutes for the hot water tank or heat exchanger to reach temperatureCheck your hot water timings on the control panel

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Related fault codes

S.73View →S.14View →

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.20A.21F.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.75

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