The Viessmann 7831369 Radial Fan with Continuous Variable Inverter is a motorized blower designed to regulate airflow in compatible heating systems. It uses an electronically controlled motor to adjust fan speed according to the boiler’s operating requirements, supporting efficient combustion air delivery and reliable ventilation. This component is designed for use in compatible Viess... https://www.partshnc.com/7831369-viessmann-radial-fan-nrg118-continuous-variable-inverter-120v