This paper presents the design and implementation of a modified Proportional-Integral-Derivative (PID) control strategy, named the Fractionalized PID (FrOPID), to enhance the transient and frequency responses, as well as the robustness of temperature control in electric furnaces. The FrOPID controller introduced in this study is being used for the first time to control electric furnace temperature. The FrOPID controller is an extension of the traditional PID controller, requiring the adjustment of four parameters compared to the three parameters of the traditional PID controller. The effectiveness of the proposed FrOPID approach was validated through extensive analysis of transient and frequency responses, as well as robustness analysis. The performance of the proposed HHO/FrOPID controller was then benchmarked against several other controllers, including the PID controller optimized by the original Harris Hawks Optimization (HHO) algorithm, and those tuned using advanced meta-heuristic algorithms such as the Harris Hawks Optimization-based PID (HHO/PID), Modified Electric Eel Foraging Optimization-based PID (MEEFO/PID), Electric Eel Foraging Optimization-based PID (EEFO/PID), and Whale Optimization Algorithm-based PID (WOA/PID). Simulation results demonstrate that the proposed HHO/FrOPID controller outperforms other existing controllers, offering superior and more robust performance in terms of percentage overshoot, settling time, rise time, and peak time.