Low
d.28 on Vaillant ecoFIT Pure 425

Your boiler is notifying you of a specific settings or wiring issue within an optional plug-in accessory module used to control extra components like pumps or external valves.

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

Function of relay 2 (multi-functional module)

Engineer required

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

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Related fault codes

d.27View →F.77View →

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