Low
S.36 on Vaillant Thermocompact

Your boiler is currently waiting for a signal from your thermostat or timer to tell it that the house needs heating or hot water.

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 Plus 824 828e 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 or programmer and turn the temperature setpoint upEnsure your heating timer is currently set to 'ON'Check if your hot water cylinder thermostat is satisfied

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