High
b7 on Viessmann Vitorond 100

Your boiler's internal computer is missing a specific identification card needed to recognize how your heating system is configured, causing it to stop working for safety reasons.

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.

What the manual says

Manufacturer manual

boiler coding card not installed

From this model's manual
Verified against the Viessmann Vitorond 100 installation & service manual, page 32.
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 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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