Viessmann D6 Error ~repack~ 〈Updated — GUIDE〉

Because this error involves the combustion and venting system, repairs involving the fan, gas valves, or internal components should be performed by a Gas Safe registered engineer

: Because this error often involves internal wiring and the gas burner's control logic, it is highly recommended to contact a Viessmann Trained Installer or a Gas Safe registered engineer to test the circuits with a multimeter. viessmann d6 error