Medium
bA on Viessmann Vitodens 242-F FB2B

Your boiler has lost connection to the extra control unit responsible for managing your second heating zone, meaning that specific part of your heating system cannot be controlled properly.

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, extension kit for heating circuit 2 (with mixer)

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 242 F Fb2b installation & service manual.
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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Related fault codes

b0View →b1View →b5View →

All 66 fault codes on the Vitodens 242-F FB2B

Seeing a different code? Every code this model can display, in one place.

9A9C9E9F58599294A2A4A7A8A9b0b1b4b5b7b8bbbCbdbEbFC1C2C3C4CdCFd6d7d8dAdbdCdddEdFE0E1E3E4E5E6E7E8EAEbECEdEEEFF0F1F2F3F7F8F9FAFCFdFEFF

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