Low
d.0 on Vaillant Ecomax Condensing 600/800 series

Your boiler is currently operating in a temporary status mode to calibrate its power output, rather than indicating a fault that requires repair.

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

Part load setting

Engineer required

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

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