EBM PAPST Centrifugal fan 3956 9282708100

The EBM PAPST Centrifugal fan 3956, SKU 9282708100, is a compact direct-drive fan designed for air exchange in burner and boiler systems. It has a flow rate of 31 GPH, a rotation speed of 1550 rpm, and dimensions of 92x92x25 mm. This fan supplies combustion air and, in room-sealed appliances, helps evacuate flue gases. In modulating premix burners, its speed controls the firing rate.

When selecting a replacement fan of this type, ensure the required air flow and pressure match the system's needs. Verify the outlet orientation (radial or tangential, and discharge angle), impeller diameter, supply voltage, and control mode (fixed mains voltage, PWM, or 0-10 V analogue). The flange pattern must align with the existing mounting. Measure these parameters before ordering.

Typical failures include worn or seized bearings causing noise or vibration, impeller imbalance from debris, failed start-up capacitors in single-phase AC types, and speed feedback errors. A loss of speed signal or deviation from commanded speed often triggers an airflow or pressure fault, leading to boiler lockout. Inspect the impeller for build-up and check bearing condition during servicing.