Low
S.02 on Vaillant ecoTEC Pro 30

Your boiler is simply preparing its internal pump to circulate water before it begins heating your home, meaning it is operating normally.

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

Heating mode: Pump pre-run

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.00View →S.03View →S.04View →

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