Low
S.30 on Vaillant ecoFIT Pure 412

Your boiler is perfectly healthy, but it is currently waiting for a signal from your wall-mounted thermostat to tell it to start heating your home.

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

Room thermostat is blocking heating mode.

Shared across the ecoFIT Pure 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.
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 your wall thermostat or heating controller and ensure it is switched to 'On' or 'Auto'.Increase the temperature setting on your thermostat to see if the boiler activates.Check if your thermostat batteries need replacing or if it has lost its wireless connection to the receiver.

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Related fault codes

S.31View →

All 74 fault codes on the ecoFIT Pure 412

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

cond.02F.00F.01F.10F.11F.13F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.83F.85F.87F.88F.89P.00P.01P.02P.06S.0S.01S.02S.03S.04S.05S.06S.07S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.31S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109

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