Low
S.02 on Vaillant ecoTEC plus System

Your boiler is simply preparing to send hot water around your radiators and is currently checking the water flow.

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.03View →S.04View →

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