Medium
F.66 on Vaillant aquaPLUS

Your boiler is having trouble communicating with its control screen, which means you cannot see or change its settings.

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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

Display fault | Display defect; fault in the connection to the display; electronics defect

Engineer required

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

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