Low
S.36 on Vaillant Combi Compact 242EB

Your boiler is currently set to a mode where it isn't asking for heat because it doesn't think any is needed based on your external controls.

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.

Technical description

Not heating demand form low voltage

DIY fix possible

Check that your room thermostat is turned up higher than the current room temperature.Ensure your programmer or heating timer is set to 'ON'.Replace the batteries in your wireless wall thermostat if it has an empty display.

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Related fault codes

S.31View →S.39View →

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