Low
S.36 on Vaillant ecoMAX

Your boiler is currently in standby mode because it has not received a signal from your thermostat 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 low voltage 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 that your room thermostat or programmer is turned up to a temperature higher than the current room temperature.Replace the batteries in your thermostat if it is a wireless model.Ensure your smart heating hub or programmer is switched on and paired with the boiler.

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