Low
Vitodens 222-F on Viessmann Vitopend 100

Your boiler is currently operating in a basic manual backup mode because it has lost communication with its external controls or sensors.

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 if the batteries in your room thermostat need replacingEnsure the boiler's control dials are set to the correct positions for your heating schedulePerform a simple reset by turning the power off and back on again

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