Low
S.30 on Vaillant ecoMAX

Your boiler is currently in standby mode because it is not receiving a signal from your thermostat or timer 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

No heating demand from external controls

From this model's manual
Verified against the Vaillant Ecomax installation & service manual, page 45.
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 room thermostat is set to a higher temperature than the current room temperature.Ensure your timer or programmer is set to 'On' or 'Timed' mode.Verify that the battery in your wireless thermostat is not flat.Check if your smart home bridge or receiver is powered on and connected to the internet.

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Related fault codes

S.31View →S.32View →

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