Low
C5:20 on Viessmann Vitodens 100-W / 200-W

Your boiler has detected that the water temperature is currently lower than its minimum safety setting and is pausing to protect the system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Electronic minimum flow temperature limit 20°C

Engineer required

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

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