What does the Vaillant S.05 fault code mean?

Your boiler is briefly keeping the internal fan and pump running to safely cool down the heat exchanger after a heating cycle.

How much does it cost to fix Vaillant error code S.05?

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

Vaillant S.05 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Heatingmode:Pump/fanoverrun

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.

What causes this fault?

This is a normal part of the boiler's operation and occurs when the heating has finished its cycle. The boiler keeps the internal pump and fan running for a few minutes to dissipate residual heat and safely cool down the internal components. It is not a breakdown and the system will resume normal operation as soon as the cooling process is complete.

DIY fix possible

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

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Related fault codes

S.07View →S.08View →

All 170 fault codes on the ecoTEC Plus 620

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

con d.00 D.000 d.01 d.02 d.04 d.05 d.06 d.07 d.08 d.09 d.10 d.11 d.13 d.14 d.15 d.16 d.17 d.18 d.19 d.20 d.21 d.22 d.23 d.24 d.25 d.27 d.28 d.31 d.33 d.34 d.35 d.36 d.39 d.40 d.41 d.43 d.45 d.47 d.50 d.51 d.58 d.60 d.61 d.62 d.64 d.65 d.66 d.67 d.68 d.69 d.70 F.00 F.0 F.01 F.1 F.10 F.11 F.12 F.13 F.20 F.22 F.23 F.24 F.25 F.27 F.28 F.29 F.32 F.33 F.49 F.61 F.62 F.63 F.64 F.65 F.67 F.68 F.70 F.71 F.72 F.73 F.74 F.75 F.76 F.77 F.78 F.83 F.84 F.85 F.86 F.87 F.88 F.89 F.91 F.92 F.97 F22 F70 P.00 P.0 P.01 P.1 P.02 P.2 P.3 P.4 P.5 P.06 P.6 P.07 S.0 S.01 S.1 S.02 S.2 S.03 S.3 S.04 S.4 S.5 S.06 S.6 S.07 S.7 S.08 S.8 S.10 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.33 S.34 S.36 S.39 S.41 S.42 S.46 S.53 S.54 S.88 S.91 S.96 S.97 S.98 S.99 S.108 S.109 T.02 T.03 T.04 T.05 T.06 T.08

Your boiler is briefly keeping the internal fan and pump running to safely cool down the heat exchanger after a heating cycle.

What the manual says

What causes this fault?

DIY fix possible

Avoid the next call-out bill

Related fault codes

All 170 fault codes on the ecoTEC Plus 620

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