Impellers

The impeller is the rotating fan wheel at the heart of a forced-draught burner. Mounted directly on the motor shaft, it draws combustion air into the blast tube and accelerates it towards the nozzle assembly, establishing the air pressure and flow profile on which stable flame formation depends. Without the correct impeller, neither air throughput nor the air-to-fuel ratio can be maintained within the tolerances the burner requires.

Selecting the right impeller means matching several interdependent parameters: wheel diameter, blade geometry and angle, bore diameter and shaft keyway or set-screw pattern, and the rotation direction. Flow rate at a given static pressure and motor speed must correspond to the original design specification. If you are working from a superseded part number — whether from De Dietrich, Master or any other manufacturer — cross-referencing against the original order number or the appliance model designation will confirm a compatible replacement.