Low
S.8 on Vaillant Ecomax Condensing 600/800 series

Your boiler is perfectly healthy and is simply pausing between heating cycles to prevent unnecessary wear and excessive fuel consumption.

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

Anti cycling mode (heating operation)

Engineer required

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

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