Medium
F.517 on Viessmann Vitodens 100-W WB1A

Your boiler has lost the digital connection to its wall-mounted remote control unit, meaning it can no longer receive instructions on when to heat your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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

What the manual says

Manufacturer manual

Communication error, Vitotrol wired remote control

From this model's manual
Verified against the Viessmann Vitodens 100 W Wb1a installation & service manual, page 97.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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