The Dayton 1TDU8 is a direct replacement blower motor engineered to restore airflow in HVAC, furnace, and ventilation systems. Rated at 223 cubic feet per minute with dual-speed operation at 2600/2750 RPM, this 115V motor runs on both 50 and 60 Hz power and is also catalogued as NBK Parts number 20533. It replaces the discontinued Dayton model 4C826 on a drop-in basis.
When your blower motor fails, a precise replacement matters. The 1TDU8 matches the physical envelope and electrical ratings of the original 4C826, so you can swap it in without rewiring or fabricating mounts. At 6 lbs and with a compact overall footprint of 14-3/4 in wide x 3-5/8 in deep x 4-3/4 in tall, it fits the same cavity as the unit it replaces.
Dual-speed operation (2600 RPM at 50 Hz / 2750 RPM at 60 Hz) and a low amp draw of 0.45/0.60A make this motor well suited for continuous-duty residential and light commercial HVAC applications. Class B insulation and ball bearings deliver long service life even in elevated-temperature environments.
Runs at 2600 RPM (50 Hz) or 2750 RPM (60 Hz) to match either power grid frequency without hardware changes.
Ball bearings replace bushing-style designs for quieter operation and longer service intervals in continuous-duty use.
Built-in thermal overload protector shuts the motor down if temperature exceeds safe limits, then resets automatically once cooled.
Class B rated windings handle sustained operating temperatures up to 266 deg F (130 deg C), providing a meaningful safety margin for HVAC duty cycles.
This motor is the current production replacement for the following part numbers:
If your system currently carries one of those part numbers on the motor nameplate or service manual, the 1TDU8 is the correct replacement.
Proper airflow depends on matching the scroll housing interface precisely. The 1TDU8 uses a 2-1/2 in inlet diameter and a 4-5/8 in wide by 1-5/8 in tall outlet -- dimensions that align with the ductwork and housing collars designed around the 4C826. The blower wheel itself measures 2-7/8 in diameter by 3.7 in wide.