Low
S.40 on Vaillant Combi Compact 282EB

Your boiler is currently running at a lower power level because it has detected a minor internal issue and is protecting itself from damage while still trying to provide some heat.

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

Comfort safety mode active

DIY fix possible

Check that your radiator valves are fully openEnsure the boiler pressure is between 1.0 and 1.5 barPress the reset button (flame symbol) to see if the status clears

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Related fault codes

F.22View →F.23View →F.24View →

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