Century 4UU21 Single Phase Room Air Conditioner Motor

Century 4UU21 is a single‑phase room air conditioner motor rated at 1/8 horsepower with three speeds and a nameplate speed of 1,075 RPM, designed as a direct replacement blower motor for standard residential window and through‑the‑wall air conditioners. Operated from 115V AC and configured for counterclockwise lead end (CCWLE) rotation, this PSC (permanent split capacitor) motor is built with a two‑shaft arrangement to fit common blower assemblies. The 4UU21 model is part of Century’s line of room‑air‑conditioner motors and is typically selected when a compact, low‑power blower is required to deliver controlled airflow across a range of cooling loads. In practice, the three‑speed capability enables trimming of fan speed to balance comfort and energy efficiency in compact cooling units. The combination of a 1/8 HP rating and 1,075 RPM produces moderate airflow suitable for replacement in many draw‑through and blow‑through AC configurations, offering a straightforward substitution for original equipment where the voltage and rotation direction match.