Low
S.00 on Vaillant ecoTEC plus 630 VU 306/5-5 R6

Your boiler is currently on standby because your thermostat or timer is not asking for any heating or hot water.

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: No heat demand: Heating has no heat demand. The burner is off.

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Pro Ecotec Plus Regular 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 that your room thermostat is set higher than the current room temperature.Check your heating timer or programmer to ensure it is currently scheduled to be on.Try turning the heating off and back on at the thermostat to reset the demand.

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Related fault codes

S.01View →S.02View →S.04View →

All 113 fault codes on the ecoTEC plus 630 VU 306/5-5 R6

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

D.000F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.25F.26F.27F.28F.29F.32F.42F.49F.52F.53F.54F.55F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.77F.78F.80F.81F.82F.83F.84F.85F.90F.91F.92F.93F.94P.00P.0P.01P.02P.06S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.40S.41S.42S.46S.53S.54S.57S.58S.61S.62S.63S.76S.88S.92S.93S.96S.97S.98S.99T.02T.03T.04T.05T.06T.08

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