Low
S.28 on Vaillant ecoTEC Pro 30

Your boiler is taking a short, scheduled break to prevent the system from getting too hot and wearing out the parts prematurely.

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

Hot water burner anti-cycling time

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

S.27View →S.53View →

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