Low
S.30 on Vaillant Thermocompact

Your boiler is currently in standby mode because it has not received a request for heat from your wall thermostat or timer.

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

No heating demand from external controls

From this model's manual
Verified against the Vaillant Turbomax Plus 824 828e installation & service manual, page 38.
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 wall thermostat is set to a higher temperature than the current room temperature.Ensure your programmer or heating timer is switched to 'On' or 'Timed' mode.Verify that any smart heating apps or bridge devices are connected and have not lost their signal.

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