Ventilateur ebmpapst WZD800GG0301

This is a centrifugal fan from EBM PAPST, catalogue article 377.145.645, manufacturer code WZD800-GG03-01. Fans of this type supply combustion air to burners and, in room-sealed appliances, also drive the flue gases out of the system. In modulating premix boilers, the fan speed directly sets the firing rate; the burner control varies the speed and the gas valve follows in proportion. When selecting a replacement, the key parameters are air flow and static pressure, the direction and orientation of the outlet (scroll position), impeller diameter, voltage, and control mode – which can be mains (on/off), PWM, or 0‑10 V signal. The flange pattern and mounting dimensions must match the burner’s design. Common failure modes include worn bearings, imbalance caused by deposits on the impeller blades, a failed starting capacitor, and speed feedback faults that the boiler reports as an airflow or pressure error. Always confirm the required rotation direction and outlet orientation before ordering, as these differ between applications.