Low
S.36 on Vaillant Turbomax 824/828

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 low voltage 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 your room thermostat is set to a temperature higher than the current room temperatureEnsure your external timer or programmer is set to an 'ON' positionCheck that your boiler's internal heating dial is turned up to a reasonable setting

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