Medium
C6:75 on Viessmann Vitodens 100-W / 200-W

Your boiler has detected that the water temperature is too hot and has automatically limited it to prevent damage to your heating system.

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

Electronic maximum flow temperature limit at 75°C

Engineer required

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

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