Low
Vitotronic 050/200-H on Viessmann Vitopend 111

Your boiler's frost protection mode has been triggered because the outside temperature has dropped to freezing, causing the pump to run continuously to prevent pipe damage.

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

Activates after 0°C / 32°F outdoor temperature

DIY fix possible

Check that outdoor sensor cables are not damaged or covered in iceEnsure your heating system pressure is between 1.0 and 1.5 barWait for external temperatures to rise; the message should clear automatically once the weather warms up

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