The LiftMaster 29-1050-B2 Capacitor is a motor start capacitor rated at 340–408 µF (MFD) designed for select LiftMaster commercial and industrial door operators. As a start component for single‑phase AC motors, it delivers the high inrush current needed to generate starting torque, helping the operator begin moving heavy overhead doors smoothly and reliably. This direct-replacement part is commonly used when an operator motor hums, struggles to start, or intermittently trips on startup, and it is intended for units that specifically list 29-1050-B2 or a 340–408 µF start capacitor in their parts documentation.
Use cases include repair and maintenance of LiftMaster commercial garage door operators in warehouses, loading docks, and other high‑duty environments. For accuracy, verify compatibility against your operator’s service manual or parts diagram before ordering. Installation should be performed with power locked out; capacitors can retain an electrical charge, so discharge procedures and applicable safety practices must be followed. Mount in the existing capacitor bracket or enclosure and reconnect leads as originally configured; no programming is required after replacement. This OEM category replacement helps restore proper startup performance and reliability for LiftMaster operators built to use a 340–408 µF start capacitor.