Low
S.30 on Vaillant Turbomax 824/828

Your boiler is currently on standby because it hasn't received a signal from your thermostat or timer to turn on the heating.

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 824 828 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 room thermostat or smart controller is set to a temperature higher than the current room temperatureEnsure your external timer or programmer is set to an 'ON' periodCheck if any external boiler interface or zone valves are responding to the heating signal

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Related fault codes

S.31View →S.32View →

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