The Fasco A143 is a direct-replacement draft inducer blower motor engineered for residential and light-commercial gas furnaces from Trane, Emerson, Jakel, Mars, and Universal. It replaces over a dozen cross-referenced part numbers and drops in with the original 3.3-inch frame diameter, 6-inch pin-housing lead, and single-speed shaded pole design. Thermal overload protection and Class B insulation are built in -- no add-ons required.
Draft inducer motors are among the most failure-prone components in forced-air gas furnaces. When the original motor wears out, bearing noise increases, start times lengthen, and eventually the furnace trips on pressure switch lockout. The Fasco A143 restores proper combustion airflow using the same 3.3-inch shaded pole frame geometry as the OEM unit it replaces, keeping installation straightforward.
This motor is also catalogued as NBK Parts 12466, which is how it ships from many HVAC distributors. If your invoice or parts list shows 12466, this is the correct unit.
Automatic reset thermal protector guards the motor winding against overheating caused by blocked flue conditions or prolonged run cycles.
Precision ball bearings support quieter operation and longer service life compared to sleeve-bearing alternatives in high-cycle furnace duty.
Winding insulation rated for 130 deg C continuous, with a design ambient limit of 104 deg F (40 deg C) -- appropriate for furnace heat exchanger cabinet environments.
6-inch lead with pin housing terminal connector matches the OEM harness on compatible Trane and Jakel assemblies -- no splicing required in most applications.
The A143 is a verified replacement for the following OEM and aftermarket part numbers. Confirm your original part number before ordering to ensure correct fitment.
This is a shaded pole, single-phase, single-speed motor -- the standard design for furnace inducer applications where a simple on/off airflow demand is all that is required. Shaded pole motors have no start capacitor and no run capacitor, simplifying both troubleshooting and replacement.
The open air-over enclosure means the motor relies on the airflow it is drawing through the inducer housing for cooling. Do not run the motor outside of its intended inducer assembly housing; sustained operation without proper airflow will shorten motor life.
Before removing the failed motor, photograph or sketch the existing wiring orientation and inducer housing mounting position. The Fasco A143 uses a standard 3.3-inch frame, but the shaft orientation (clockwise or counterclockwise rotation viewed from shaft end) and housing flange position must match the original for correct draft airflow direction.