High
Connection on Vaillant ecoFIT Pure 825

Your boiler's main control panel is unable to "talk" to the computer brain inside the unit, meaning it cannot receive or process your commands.

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

No communication between the PCB and the user interface

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.70View →F.71View →

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