High
P.03 on Vaillant ecoFIT Pure 418

Your boiler is confused because it is looking for a smart controller that isn't connected, causing it to stop its automatic setup process.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Check programme for system without eBUS controller.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.49View →F.22View →P.01View →

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