Low
S.0 on Vaillant Home System

Your boiler is working perfectly well but is currently resting because your thermostat or timer is not telling it to turn the heating on.

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 mode: No requirement

From this model's manual
Verified against the Vaillant Home System installation & service manual, page 32.
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 turned up higher than the current room temperature.Ensure your heating programmer or timer is set to an 'on' period.Check that the batteries in your wireless thermostat have not run out.

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