Low
Viessmann boilers on Viessmann Vitola Biferral

Your boiler is operating in a standard control mode, which usually means it is running based on its internal settings rather than an external demand or a specific fault being triggered.

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

Control mode

DIY fix possible

Check that your room thermostat or programmer is set to the desired temperatureEnsure the boiler power switch is turned onCheck for any other symbols on the display that might indicate a specific timer or weather compensation setting is active

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