Abstract: This invention relates to an electric cartridge heater and a method of operation, suitable for use in producing high purity silicon in solar cells or solar modules. The apparatus includes a single-piece elongated heater bar having a length, a first end, and a second end. The apparatus also includes a slot beginning at the first end and running a portion of the length, and the slot dividing the heater bar into a first arm and a second arm. An elbow at the second end joins the first arm and the second arm together. The apparatus also includes a first electrode in electrical communication with the first arm, and a second electrode in electrical communication with the second arm.