What does the Vaillant S.10 fault code mean?

Your boiler has detected that you have turned on a hot water tap and is currently working to heat water for you.

How much does it cost to fix Vaillant error code S.10?

Cost varies. Contact a Gas Safe registered engineer for a quote.

Vaillant S.10 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Hot water demand

From this model's manual

Verified against the Vaillant/Vaillant Ecotec Plus Pro 839592 05 2006 installation & service manual, page 43.

What causes this fault?

This code appears when the boiler's internal flow sensor detects water moving through the pipes after you open a hot water tap. It physically indicates that the internal diverter valve has shifted position to prioritise heating your water instead of your radiators. This is a normal functional message and does not indicate a mechanical failure or a breakdown.

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

Find a Gas Safe engineer

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Boiler cover options

Avoid the next call-out bill

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Related fault codes

S.11View →S.13View →S.14View →

All 135 fault codes on the ecoTEC plus 612 R1 VU GB 126/3-5

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

35 96 con Connection D,11 D.0 D.1 D.2 D.3 D.4 D.5 D.7 D.8 D.9 D.10 D.12 D.13 D.17 D.18 D.20 D.22 D.23 D.25 D.27 D.28 D.30 D.33 D.34 D.35 D.40 D.41 D.44 D.47 D.50 D.51 D.60 D.61 D.64 D.65 D.67 D.68 D.69 D.70 D.71 D.72 D.75 D.76 D.77 D.78 D.80 D.81 D.82 D.83 D.84 D.90 D.91 D.93 D.96 D.97 F.0 F.1 F.10 F.11 F.13 F.20 F.22 F.23 F.24 F.25 F.27 F.28 F.29 F.32 F.49 F.61 F.62 F.63 F.64 F.65 F.67 F.70 F.71 F.72 F.73 F.74 F.75 F.76 F.77 F.78 F70 P.0 P.1 P.2 P.3 P.4 P.5 P.6 S. 2 S. 5 S.0 S.1 S.3 S.4 S.6 S.7 S.8 S.11 S.13 S.14 S.15 S.16 S.17 S.20 S.21 S.22 S.23 S.24 S.25 S.26 S.27 S.28 S.30 S.31 S.32 S.34 S.36 S.41 S.42 S.52 S.53 S.54 S.96 S.97 S.98

Your boiler has detected that you have turned on a hot water tap and is currently working to heat water for you.

What the manual says

What causes this fault?

DIY fix possible

Avoid the next call-out bill

Related fault codes

All 135 fault codes on the ecoTEC plus 612 R1 VU GB 126/3-5

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