Low
S.30 on Vaillant Turbomax Plus

Your boiler is currently idle because it is not receiving 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 Plus 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 is turned up higher than the current room temperature.Ensure your heating programmer or clock is set to an 'On' period.Check for flat batteries in your wireless thermostat and replace them if necessary.

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S.31View →S.33View →

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