Medium
P.03 on Vaillant ecoFIT Pure 825

Your boiler is currently waiting for a signal from your thermostat to tell it how to run, but it isn't receiving the correct communication.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Check programme for system without eBUS controller.

Engineer required

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

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Related fault codes

F.76View →F.77View →

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