Low
S.2 on Vaillant Ecomax Condensing 600/800 series

Your boiler is currently preparing to ignite and is circulating water through the system, which is a normal part of the startup sequence.

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

Pump running – pre ignition (heating operation)

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.0View →S.1View →S.3View →

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