Medium
0d on Viessmann Vitodens

Your boiler is having trouble communicating with an extra piece of equipment that controls heating for a specific zone of your home, which may result in that area not heating up properly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

Extension kit for one heating circuit with mixer

Engineer required

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

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Related fault codes

0bView →0cView →0eView →

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