Low
S.08 on Vaillant ecoTEC plus 612 VU GB 126/3-5

Your boiler is taking a temporary, normal rest to avoid turning on and off too frequently.

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

Anti cycling mode

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus Pro 839592 00 2004 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

Wait a few minutes for the timer to naturally expire and the boiler to restart.Check that your heating and hot water controls are not calling for heat too rapidly.Ensure radiators are not all turned down or blocked, which can restrict water flow.

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Related fault codes

S.00View →S.91View →

All 119 fault codes on the ecoTEC plus 612 VU GB 126/3-5

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

d.00d.01d.02d.03d.05d.06d.07d.08d.09d.10d.11d.17d.18d.19d.22d.23d.25d.26d.30d.33d.34d.35d.36d.40d.41d.44d.47d.50d.51d.60d.61d.64d.65d.67d.68d.69d.70d.71d.72d.73d.75d.76d.77d.78d.80d.81d.82d.83d.84d.90d.91d.93d.97F.00F.01F.02F.10F.11F.13F.20F.22F.23F.24F.27F.28F.29F.32F.60F.61F.62F.63F.64F.65F.70F.71F.72F.73F.74F.75F.76P.1P.2P.3P.4P.5P.6S.00S.01S.02S.03S.04S.05S.06S.07S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.36S.53S.54S.76

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