A direct-fit replacement condenser fan motor engineered to restore cooling performance in residential and light-commercial condensing units. The Genteq 3905 (also sold as NBK 20408) drops in where Carrier HC39GE237, HC39GE237A, and Dayton 6DLL0 motors have failed -- no rewiring, no fabrication, no guesswork. Built with automatic thermal protection, Class B insulation, and a totally enclosed non-ventilated (TENV) steel shell for reliable continuous-duty operation outdoors.
When a condenser fan motor burns out, you want a part that goes in clean the first time. The Genteq 3905 matches the electrical and mechanical profile of the original Carrier and Dayton motors it replaces, including the stud mount pattern, 1/2-inch flat-keyed shaft, and 208-230V single-phase wiring. There is no need to modify the mounting bracket or source a separate capacitor adapter.
This is a permanent split capacitor (PSC) motor -- it requires an external run capacitor, which is standard equipment on any unit that originally used these Carrier or Dayton motors. If you are sourcing this motor as a field replacement, confirm the existing capacitor matches the motor's rated value before startup.
Built-in thermal overload shuts the motor down before heat damage occurs and resets automatically once the motor cools -- reducing service calls caused by winding failures.
Totally enclosed non-ventilated construction keeps contaminants, insects, and moisture out of the windings -- a must for exposed outdoor condenser applications.
Rated for continuous winding temperatures up to 130 deg C (266 deg F), providing a meaningful safety margin over the operating temperatures common in condenser fan service.
8-inch stud mount configuration and vertical shaft-down orientation match the factory bracket on compatible Carrier condensing units for a bolt-on swap.
PSC motors are the industry standard for condenser fan duty. They run quietly, start smoothly without a start capacitor, and draw a steady 1.4 amps at 208-230V -- well within the original equipment circuit rating. Single-speed, single-phase operation keeps the control wiring simple.
This motor is a confirmed replacement for the following OEM and distribution part numbers:
Always verify shaft direction, mounting stud size, voltage, and RPM against the failed motor's nameplate before ordering. The 3905 is a vertical shaft-down motor -- if your application requires shaft-up orientation, a different model will be needed.
This motor uses sleeve (plain) bearings rather than ball bearings. Sleeve bearings are quieter and well-suited to vertical shaft-down condenser fan duty, but they are sensitive to mounting orientation -- do not operate this motor in a horizontal shaft position or shaft-up configuration without confirming the bearing design supports it.